化简求值(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b),a=-1,b=1

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化简求值(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b),a=-1,b=1

化简求值(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b),a=-1,b=1
化简求值(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b),a=-1,b=1

化简求值(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b),a=-1,b=1
很高兴为您
(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b)
=a^2-4b^2-(a-5b)^2(a+3b)
因为a=-1,b=1
所以原式=1-4-36x2=-75

(a-2b)(a+2b)-(a-5b)(a-5b)(a+3b)
=a^2-4b^2-(a-5b)^2(a+3b)

,a=-1,b=1
原式=(-1)^2-4*1-(-1-5*1)^2*(-1+3*1)
=1-4-36*2
=1-4-72
=-75

原式=a^2-4b^2-(a^2-10ab+25b^2)(a+3b)
=1-4-(1+10+25)(-1+3)
=-3-36*2
=-75

=1-4-36*2=-75