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Statement List for Metamath Proof Explorer - 7801-7900 - Page 79 of 175
TypeLabelDescription
Statement
 
Theoremseqzcl 7801 Closure of the value of the arbitrary-based recursive sequence builder.
|- S e. _V   &   |- F e. _V   =>   |- ((N e. (ZZ>=` M) /\ F:(ZZ>=` M)-->C /\ S:(C X. C)-->C) -> ((<.M, S>. seq F)` N) e. C)
 
Theoremseqzresval 7802 A restriction of its characteristic function that doesn't change the value of the seq function.
|- S e. _V   &   |- F e. _V   =>   |- (N e. (ZZ>=` M) -> ((<.M, S>. seq (F |` (M...N)))` N) = ((<.M, S>. seq F)` N))
 
Theoremseqzres 7803 The seq function is unchanged by restricting its characteristic function to the seq function's domain.
|- S e. _V   &   |- F e. _V   =>   |- (M e. ZZ -> (<.M, S>. seq (F |` (ZZ>=` M))) = (<.M, S>. seq F))
 
Theoremseqzres2 7804 The seq function is unchanged by substituting its characteristic function with a restricted class builder based on that function.
|- S e. _V   &   |- F e. _V   =>   |- (M e. ZZ -> (<.M, S>. seq ({<.k, y>. | y = (F` k)} |` ZZ)) = (<.M, S>. seq F))
 
Theoremserzcl1i 7805 The partial sums in an infinite series of complex terms are complex.
|- F:(ZZ>=` M)-->CC   =>   |- (N e. (ZZ>=` M) -> ((<.M, + >. seq F)` N) e. CC)
 
Theoremdfseq0 7806 Alternate version of df-seq0 7777.
|- seq0 = {<.<.f, g>., h>. | h = (<.0, f>. seq g)}
 
Theoremser0cl1i 7807 The partial sums in an infinite 0-based series of complex terms are complex.
|- F:NN0-->CC   =>   |- (N e. NN0 -> (( + seq0 F)` N) e. CC)
 
Theoremser0fi 7808 A 0-based infinite series is a function from NN0 to CC.
|- F:NN0-->CC   =>   |- ( + seq0 F):NN0-->CC
 
Theoremser00i 7809 The value of the first term in a 0-based infinite series.
|- F = {<.k, y>. | (k e. NN0 /\ y = A)}   &   |- B e. _V   &   |- (k = 0 -> A = B)   =>   |- (( + seq0 F)` 0) = B
 
Theoremser0p1i 7810 The value of the next term in a 0-based infinite series.
|- F = {<.k, y>. | (k e. NN0 /\ y = A)}   &   |- B e. _V   &   |- (k = (N + 1) -> A = B)   =>   |- (N e. NN0 -> (( + seq0 F)` (N + 1)) = ((( + seq0 F)` N) + B))
 
Integer powers
 
Syntaxcexp 7811 Extend class notation to include exponentiation of a complex number to an integer power.
class ^
 
Definitiondf-exp 7812 Define exponentiation to nonnegative integer powers. This definition is not meant to be used directly; instead, exp0 7814 and expp1 7817 provide a the standard recursive definition. The up-arrow notation is used by Donald Knuth for iterated exponentiation (Science 194, 1235-1242, 1976) and is convenient for us since we don't have superscripts. See expnnval 7815 for a description of how the recursive sequence builder is used. 10-Jun-2005: The definition was extended to include zero exponents, so that 0^0 = 1 per the convention of Definition 10-4.1 of [Gleason] p. 134. (Based on definition contributed by Raph Levien, 15-Oct-2004.)
|- ^ = {<.<.x, y>., z>. | ((x e. CC /\ y e. NN0) /\ z = if(y = 0, 1, (( x. seq1 (NN X. {x}))` y)))}
 
Theoremexpval 7813 Value of exponentiation to nonnegative integer powers.
|- ((A e. CC /\ N e. NN0) -> (A^N) = if(N = 0, 1, (( x. seq1 (NN X. {A}))` N)))
 
Theoremexp0 7814 Value of a complex number raised to the 0th power. Note that under our definition, 0^0 = 1, following the convention used by Gleason. Part of Definition 10-4.1 of [Gleason] p. 134.
|- (A e. CC -> (A^0) = 1)
 
Theoremexpnnval 7815 Value of exponentiation to natural number powers. NN X. {A} is the constant function with value A. The seq1 operation produces the sequence A, A x. A, (A x. A) x. A,... that we evaluate at index B.
|- ((A e. CC /\ B e. NN) -> (A^B) = (( x. seq1 (NN X. {A}))` B))
 
Theoremexp1 7816 Value of a complex number raised to the first power.
|- (A e. CC -> (A^1) = A)
 
Theoremexpp1 7817 Value of a complex number raised to a nonnegative integer power plus one. Part of Definition 10-4.1 of [Gleason] p. 134.
|- ((A e. CC /\ N e. NN0) -> (A^(N + 1)) = ((A^N) x. A))
 
Theoremexpcllem 7818 Lemma for proving nonnegative integer exponentiation closure laws.
 
Theoremnnexpcl 7819 Closure of exponentiation of nonnegative integers.
|- ((A e. NN /\ N e. NN0) -> (A^N) e. NN)
 
Theoremnn0expcl 7820 Closure of exponentiation of nonnegative integers.
|- ((A e. NN0 /\ N e. NN0) -> (A^N) e. NN0)
 
Theoremzexpcl 7821 Closure of exponentiation of integers.
|- ((A e. ZZ /\ N e. NN0) -> (A^N) e. ZZ)
 
Theoremqexpcl 7822 Closure of exponentiation of rationals.
|- ((A e. QQ /\ N e. NN0) -> (A^N) e. QQ)
 
Theoremreexpcl 7823 Closure of exponentiation of reals.
|- ((A e. RR /\ N e. NN0) -> (A^N) e. RR)
 
Theoremexpcl 7824 Closure law for nonnegative integer exponentiation.
|- ((A e. CC /\ N e. NN0) -> (A^N) e. CC)
 
Theoremrpexpcl 7825 Closure law for exponentiation of positive reals.
|- ((A e. RR+ /\ N e. NN0) -> (A^N) e. RR+)
 
Theoremexpm1t 7826 Exponentiation in terms of predecessor exponent.
|- ((A e. CC /\ N e. NN) -> (A^N) = ((A^(N - 1)) x. A))
 
Theorem1exp 7827 Value of one raised to a nonnegative integer power.
|- (N e. NN0 -> (1^N) = 1)
 
Theoremexpeq0 7828 Natural number exponentiation is 0 iff its mantissa is 0.
|- ((A e. CC /\ N e. NN) -> ((A^N) = 0 <-> A = 0))
 
Theoremexpne0 7829 Natural number exponentiation is nonzero iff its mantissa is nonzero.
|- ((A e. CC /\ N e. NN) -> ((A^N) =/= 0 <-> A =/= 0))
 
Theoremexpne0i 7830 Nonnegative integer exponentiation is nonzero if its mantissa is nonzero.
|- ((A e. CC /\ A =/= 0 /\ N e. NN0) -> (A^N) =/= 0)
 
Theoremexpgt0 7831 Nonnegative integer exponentiation with a positive mantissa is positive.
|- ((A e. RR /\ N e. NN0 /\ 0 < A) -> 0 < (A^N))
 
Theorem0exp 7832 Value of zero raised to a natural number power.
|- (N e. NN -> (0^N) = 0)
 
Theoremexpge0 7833 Nonnegative integer exponentiation with a nonnegative mantissa is nonnegative.
|- ((A e. RR /\ N e. NN0 /\ 0 <_ A) -> 0 <_ (A^N))
 
Theoremexpgt1 7834 Natural number exponentiation with a mantissa greater than 1 is greater than 1.
|- ((A e. RR /\ N e. NN /\ 1 < A) -> 1 < (A^N))
 
Theoremexpge1 7835 Nonnegative integer exponentiation with a mantissa greater than or equal to 1 is greater than or equal to 1.
|- ((A e. RR /\ N e. NN0 /\ 1 <_ A) -> 1 <_ (A^N))
 
Theoremmulexp 7836 Natural number exponentiation of a product. Proposition 10-4.2(c) of [Gleason] p. 135, restricted to nonnegative integer exponents.
|- ((A e. CC /\ B e. CC /\ N e. NN0) -> ((A x. B)^N) = ((A^N) x. (B^N)))
 
Theoremexprec 7837 Nonnegative integer exponentiation of a reciprocal.
|- ((A e. CC /\ A =/= 0 /\ N e. NN0) -> ((1 / A)^N) = (1 / (A^N)))
 
TheoremexprecOLD 7838 Nonnegative integer exponentiation of a reciprocal.
|- ((A e. CC /\ N e. NN0 /\ A =/= 0) -> ((1 / A)^N) = (1 / (A^N)))
 
Theoremexpadd 7839 Sum of exponents law for nonnegative integer exponentiation. Proposition 10-4.2(a) of [Gleason] p. 135.
|- ((A e. CC /\ M e. NN0 /\ N e. NN0) -> (A^(M + N)) = ((A^M) x. (A^N)))
 
Theoremexpmul 7840 Product of exponents law for natural number exponentiation. Proposition 10-4.2(b) of [Gleason] p. 135, restricted to nonnegative integer exponents.
|- ((A e. CC /\ M e. NN0 /\ N e. NN0) -> (A^(M x. N)) = ((A^M)^N))
 
Theoremexpsub 7841 Exponent subtraction law for nonnegative integer exponentiation.
|- ((((A e. CC /\ A =/= 0) /\ M e. NN0 /\ N e. NN0) /\ N <_ M) -> (A^(M - N)) = ((A^M) / (A^N)))
 
TheoremexpsubOLD 7842 Exponent subtraction law for nonnegative integer exponentiation.
|- (((A e. CC /\ M e. NN0 /\ N e. NN0) /\ (A =/= 0 /\ N <_ M)) -> (A^(M - N)) = ((A^M) / (A^N)))
 
Theoremexpm1 7843 Value of a complex number raised to a nonnegative integer power minus one.
|- ((A e. CC /\ A =/= 0 /\ N e. NN) -> (A^(N - 1)) = ((A^N) / A))
 
Theoremexpdiv 7844 Nonnegative integer exponentiation of a quotient.
|- ((A e. CC /\ (B e. CC /\ B =/= 0) /\ N e. NN0) -> ((A / B)^N) = ((A^N) / (B^N)))
 
Theoremexpordi 7845 Ordering relationship for exponentiation.
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ (1 < A /\ M < N)) -> (A^M) < (A^N))
 
Theoremexpcan 7846 Cancellation law for exponentiation.
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ 1 < A) -> ((A^M) = (A^N) <-> M = N))
 
Theoremexpord 7847 Ordering law for exponentiation.
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ 1 < A) -> (M < N <-> (A^M) < (A^N)))
 
Theoremexpwordi 7848 Weak ordering relationship for exponentiation.
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ (1 <_ A /\ M <_ N)) -> (A^M) <_ (A^N))
 
Theoremexpord2 7849 The power of a positive number smaller than 1 decreases as its exponent increases.
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ (0 < A /\ A < 1)) -> (M < N <-> (A^N) < (A^M)))
 
Theoremexpword2i 7850 Weak ordering relationship for exponentiation. (Contributed by Paul Chapman, 14-Jan-2008.)
|- (((A e. RR /\ M e. NN0 /\ N e. NN0) /\ (0 < A /\ A <_ 1 /\ M < N)) -> (A^N) <_ (A^M))
 
Theoremexpmwordi 7851 Weak mantissa ordering relationship for exponentiation.
|- (((A e. RR /\ B e. RR /\ N e. NN0) /\ (0 <_ A /\ A <_ B)) -> (A^N) <_ (B^N))
 
Theoremexple1 7852 Nonnegative integer exponentiation with a mantissa between 0 and 1 inclusive is less than or equal to 1. (Contributed by Paul Chapman, 29-Dec-2007.)
|- (((A e. RR /\ 0 <_ A /\ A <_ 1) /\ N e. NN0) -> (A^N) <_ 1)
 
Theoremexpubnd 7853 An upper bound on A^N when 2 <_ A.
|- ((A e. RR /\ N e. NN0 /\ 2 <_ A) -> (A^N) <_ ((2^N) x. ((A - 1)^N)))
 
Theoremsqval 7854 Value of the square of a complex number. (Contributed by Raph Levien, 10-Apr-2004.)
|- (A e. CC -> (A^2) = (A x. A))
 
Theoremsqneg 7855 The square of the negative of a number.)
|- (A e. CC -> (-uA^2) = (A^2))
 
Theoremsqcl 7856 Closure of square.
|- (A e. CC -> (A^2) e. CC)
 
Theoremsqmul 7857 Distribution of square over multiplication.
|- ((A e. CC /\ B e. CC) -> ((A x. B)^2) = ((A^2) x. (B^2)))
 
Theoremsqeq0 7858 A number is zero iff its square is zero.
|- (A e. CC -> ((A^2) = 0 <-> A = 0))
 
Theoremsqvali 7859 Value of square. Inference version.
|- A e. CC   =>   |- (A^2) = (A x. A)
 
Theoremsqcli 7860 Closure of square.
|- A e. CC   =>   |- (A^2) e. CC
 
Theoremsqeq0i 7861 A number is zero iff its square is zero.
|- A e. CC   =>   |- ((A^2) = 0 <-> A = 0)
 
Theoremsqmuli 7862 Distribution of square over multiplication.
|- A e. CC   &   |- B e. CC   =>   |- ((A x. B)^2) = ((A^2) x. (B^2))
 
Theoremsqdivi 7863 Distribution of square over division.
|- A e. CC   &   |- B e. CC   &   |- B =/= 0   =>   |- ((A / B)^2) = ((A^2) / (B^2))
 
Theoremsqrecii 7864 Square of reciprocal.
|- A e. CC   &   |- A =/= 0   =>   |- ((1 / A)^2) = (1 / (A^2))
 
Theoremsqne0 7865 A number is nonzero iff its square is nonzero.
|- (A e. CC -> ((A^2) =/= 0 <-> A =/= 0))
 
Theoremresqcl 7866 Closure of the square of a real number.
|- (A e. RR -> (A^2) e. RR)
 
Theoremsqgt0 7867 The square of a nonzero real is positive.
|- ((A e. RR /\ A =/= 0) -> 0 < (A^2))
 
Theoremresqcli 7868 Closure of square in reals.
|- A e. RR   =>   |- (A^2) e. RR
 
Theoremlt2sqi 7869 The square function on nonnegative reals is strictly monotonic.
|- A e. RR   &   |- B e. RR   =>   |- ((0 <_ A /\ 0 <_ B) -> (A < B <-> (A^2) < (B^2)))
 
Theoremle2sqi 7870 The square function on nonnegative reals is monotonic.
|- A e. RR   &   |- B e. RR   =>   |- ((0 <_ A /\ 0 <_ B) -> (A <_ B <-> (A^2) <_ (B^2)))
 
Theoremsq11i 7871 The square function is one-to-one for nonnegative reals.
|- A e. RR   &   |- B e. RR   =>   |- ((0 <_ A /\ 0 <_ B) -> ((A^2) = (B^2) <-> A = B))
 
Theoremsqgt0i 7872 The square of a nonzero real is positive.
|- A e. RR   =>   |- (A =/= 0 -> 0 < (A^2))
 
Theoremsqge0i 7873 A square of a real is nonnegative.
|- A e. RR   =>   |- 0 <_ (A^2)
 
Theoremsq11 7874 The square function is one-to-one for nonnegative reals.
|- (((A e. RR /\ 0 <_ A) /\ (B e. RR /\ 0 <_ B)) -> ((A^2) = (B^2) <-> A = B))
 
Theoremlt2sq 7875 The square function on nonnegative reals is strictly monotonic.
|- (((A e. RR /\ 0 <_ A) /\ (B e. RR /\ 0 <_ B)) -> (A < B <-> (A^2) < (B^2)))
 
Theoremle2sq 7876 The square function on nonnegative reals is monotonic.
|- (((A e. RR /\ 0 <_ A) /\ (B e. RR /\ 0 <_ B)) -> (A <_ B <-> (A^2) <_ (B^2)))
 
Theoremle2sq2 7877 The square of a 'less than or equal to' ordering.
|- (((A e. RR /\ 0 <_ A) /\ (B e. RR /\ A <_ B)) -> (A^2) <_ (B^2))
 
Theoremsqge0 7878 A square of a real is nonnegative.
|- (A e. RR -> 0 <_ (A^2))
 
Theoremsumsqne0i 7879 The sum of two squares is nonzero iff one of its terms is nonzero.
|- A e. RR   &   |- B e. RR   =>   |- ((A =/= 0 \/ B =/= 0) <-> ((A^2) + (B^2)) =/= 0)
 
Theoremsq0 7880 The square of 0 is 0.
|- (0^2) = 0
 
Theoremsq0i 7881 If a number is zero, its square is zero. (Contributed by FL, 10-Dec-2006.)
|- (A = 0 -> (A^2) = 0)
 
Theoremsq1 7882 The square of 1 is 1.
|- (1^2) = 1
 
Theoremsq2 7883 The square of 2 is 4.
|- (2^2) = 4
 
Theoremsq3 7884 The square of 3 is 9.
|- (3^2) = 9
 
Theoremcu2 7885 The cube of 2 is 8.
|- (2^3) = 8
 
Theoremexpnass 7886 A counterexample showing that exponentiation is not associative. (Contributed by Stefan Allan and Gérard Lang, 21-Sep-2010.)
|- ((3^3)^3) < (3^(3^3))
 
Theoremsqlecan 7887 Cancel one factor of a square in a <_ comparison. Unlike lemul1 7011, the common factor A may be zero.
|- (((A e. RR /\ 0 <_ A) /\ (B e. RR /\ 0 <_ B)) -> ((A^2) <_ (B x. A) <-> A <_ B))
 
Theoremsubsq 7888 Factor the difference of two squares.
|- ((A e. CC /\ B e. CC) -> ((A^2) - (B^2)) = ((A + B) x. (A - B)))
 
Theoremsubsq2 7889 Express the difference of the squares of two numbers as a polynomial in the difference of the numbers.
|- ((A e. CC /\ B e. CC) -> ((A^2) - (B^2)) = (((A - B)^2) + ((2 x. B) x. (A - B))))
 
Theorembinom2i 7890 The square of a binomial.
|- A e. CC   &   |- B e. CC   =>   |- ((A + B)^2) = (((A^2) + (2 x. (A x. B))) + (B^2))
 
Theorembinom2aiOLD 7891 Product of sum and difference.
|- A e. CC   &   |- B e. CC   =>   |- ((A + B) x. (A - B)) = ((A^2) - (B^2))
 
Theoremsubsqi 7892 Factor the difference of two squares.
|- A e. CC   &   |- B e. CC   =>   |- ((A^2) - (B^2)) = ((A + B) x. (A - B))
 
Theoremsqeqori 7893 The squares of two complex numbers are equal iff one number equals the other or its negative. Lemma 15-4.7 of [Gleason] p. 311 and its converse.
|- A e. CC   &   |- B e. CC   =>   |- ((A^2) = (B^2) <-> (A = B \/ A = -uB))
 
Theoremsubsq0i 7894 The two solutions to the difference of squares set equal to zero.
|- A e. CC   &   |- B e. CC   =>   |- (((A^2) - (B^2)) = 0 <-> (A = B \/ A = -uB))
 
Theoremsqeqor 7895 The squares of two complex numbers are equal iff one number equals the other or its negative. Lemma 15-4.7 of [Gleason] p. 311 and its converse. (Contributed by Paul Chapman, 15-Mar-2008.)
|- ((A e. CC /\ B e. CC) -> ((A^2) = (B^2) <-> (A = B \/ A = -uB)))
 
Theorembinom2 7896 The square of a binomial. (Contributed by FL, 10-Dec-2006.)
|- ((A e. CC /\ B e. CC) -> ((A + B)^2) = (((A^2) + (2 x. (A x. B))) + (B^2)))
 
Theoremsq01 7897 If a complex number equals its square, it must be 0 or 1.
|- (A e. CC -> ((A^2) = A <-> (A = 0 \/ A = 1)))
 
Theorembernneq 7898 Bernoulli's inequality, due to Johan Bernoulli (1667-1748).
|- ((A e. RR /\ N e. NN0 /\ -u1 <_ A) -> (1 + (A x. N)) <_ ((1 + A)^N))
 
TheorembernneqOLD 7899 Bernoulli's inequality, due to Johan Bernoulli (1667-1748).
|- ((A e. RR /\ N e. NN0 /\ -u1 <_ A) -> (1 + (A x. N)) <_ ((1 + A)^N))
 
Theorembernneq2 7900 Variation of Bernoulli's inequality bernneq 7898.
|- ((A e. RR /\ N e. NN0 /\ 0 <_ A) -> (((A - 1) x. N) + 1) <_ (A^N))

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