Giúp mk vs , mk cần gấp
(a+b)(a-b)(a^2+b^2)(a^4+b^4)(a^8+b^8)(a^16+b^16)
\(\left(a+b\right)\left(a-b\right)\left(a^2+b^2\right)\left(a^4+b^4\right)\left(a^8+b^8\right)\left(a^{16}+b^{16}\right)\)
\(=\left(a^2-b^2\right)\left(a^2+b^2\right)\left(a^4+b^4\right)\left(a^8+b^8\right)\left(a^{16}+b^{16}\right)\)
\(=\left(a^4-b^4\right)\left(a^4+b^4\right)\left(a^8+b^8\right)\left(a^{16}+b^{16}\right)\)
\(=\left(a^8-b^8\right)\left(a^8+b^8\right)\left(a^{16}+b^{16}\right)\)
\(=\left(a^{16}-b^{16}\right)\left(a^{16}+b^{16}\right)\)
\(=a^{32}-b^{32}\)
Cho \(a=b+1.\) Chứng minh: \(\left(a+b\right).\left(a^2+b^2\right).\left(a^4+b^4\right).\left(a^8+b^8\right)=a^{16}-b^{16}\)
\(a+b=1\)
\(\Rightarrow a-b=1\)
\(\Rightarrow VT=\left(a+b\right).\left(a^2+b^2\right).\left(a^4+b^4\right).\left(a^8+b^8\right)\)
\(=\left(a-b\right).\left(a+b\right).\left(a^2+b^2\right).\left(a^4+b^4\right).\left(a^8+b^8\right)\)
\(=\left(a^2-b^2\right).\left(a^2+b^2\right).\left(a^4+b^4\right).\left(a^8+b^8\right)\)
\(=\left(a^4-b^4\right).\left(a^4+b^4\right).\left(a^8+b^8\right)\)
\(=\left(a^8-b^8\right).\left(a^8+b^8\right)\)
\(=\left(a^{16}-b^{16}\right)=VP\)
\(\Rightarrow\) Đpcm.
P/s: Lần sau cậu viết đề rõ ràng ra nhé.
a..(X-1)2 +(2-X)(4+2X+X2 )+3X(X+2)=17
b..(X+2)(X2 -2X+4)-X(X2 -2)=15
Tìm X
Giải nhanh giùm tớ nhé
Cho\(a+b+c=0.Cm:a^3+b^3+c^3=3abc\)
so sanh
A=2015.2016 va B=2016^2
Cho \(x+y=1\).Tính \(A=x^3+y^3+3xy\)
(a+b+c) ^2
* Tìm X
a/ ( x+2)2+ ( x-3)2 - 2(x-1)(1+x) = 9
b/ ( 3x - 1)2+ (3x+1)2- 18( x-2)(x+2) = 5
c/ ( 6x-5)2 - ( 6x +7)(6x-7) + 4( x-3) = 8
Rut gon
a,(4x-7)(16x^2+28x+49)
b,(3x+1)(9x^2-3x+1)-9x(3x^2-1)
Cho a+b+c=0. Chứng minh rằng: \(2.\left(a^5+b^5+c^5\right)=5abc.\left(a^2+b^2+c^2\right)\)
Xác định a,b,c,d thỏa mãn 1 trong những đẳng thức sau với mọi x:
x^4+ ax^2+ b= (x^2- 3x+ 2).(x^2- cx+ d)
(sử dụng đa thức đồng nhát bằng nhau)
cho x+y+x=0 xy+yz+zx=0 cmr x=y=z
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