关于同底数幂的乘法计算.(-x)²·(-x)³+2x(-x)^4;

问题描述:

关于同底数幂的乘法计算.(-x)²·(-x)³+2x(-x)^4;
(-x)²·(-x)³+2x(-x)^4;
(b-a)^m·(b-a)^n-5·(a-b)^5;
已知.x+2y-4=0,求3^x-1(1这个是次方.)·3^2y;
(-2)^2008+(-2)^2009=

(-x)²·(-x)³+2x(-x)^4;
=x^2*(-x^3)+2x*x^4
=-x^5+2x^5
=x^5
(b-a)^m·(b-a)^n-5·(a-b)^5;
=(b-a)^m·(b-a)^n-5·[-(b-a)]^5
=-(b-a)^m·(b-a)^n-5·(b-a)^5
=-(b-a)^(m+n-5+5)
=-(b-a)^(m+n)
已知.x+2y-4=0,求3^x-1(1这个是次方.)·3^2y;
x+2y-4=0
x+2y=4
3^(x-1)·3^2y
=3^(x-1+2y)
=3^(x+2y-1)
=3^(4-1)
=3^3
=27
(-2)^2008+(-2)^2009
=2^2008-2^2009
=2^2008-2*2^2008
=(1-2)*2^2008
=-2^2008