化简,再求值(写清过程)(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2
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![化简,再求值(写清过程)(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2](/uploads/image/z/4335544-64-4.jpg?t=%E5%8C%96%E7%AE%80%2C%E5%86%8D%E6%B1%82%E5%80%BC%EF%BC%88%E5%86%99%E6%B8%85%E8%BF%87%E7%A8%8B%EF%BC%89%281%29%285a%5E2-3b%5E2%29%2B%28a%5E2%2Bb%5E2%29-%285a%5E2%2B3b%5E2%29%2C%E5%85%B6%E4%B8%ADa%EF%BC%9D-1%2Cb%EF%BC%9D1%282%292%28a%5E2%2Bab%5E2%29-2%28a%5E2b-1%29-2ab%5E2-2%2C%E5%85%B6%E4%B8%ADa%EF%BC%9D-2%2Cb%EF%BC%9D2)
化简,再求值(写清过程)(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2
化简,再求值(写清过程)
(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1
(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2
化简,再求值(写清过程)(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2
(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2)
=5a^2-3b^2+a^2+b^2-5a^2-3b^2
=a^2-5b^2
=(-1)^2-5*1^2
=-4
(2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2
=2a^2+2ab^2-2a^2b+2-2ab^2-2
=2a^2-2a^2b-2
=2*(-2)^2-2*(-2)^2*2-2
=-10
(1)(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2),其中a=-1,b=1
(5a^2-3b^2)+(a^2+b^2)-(5a^2+3b^2)=5a^2-3b^2+a^2+b^2-5a^2-3b^2
=a^2+b^2-6b^2=a^2-5b^2=1-5=-4
2)2(a^2+ab^2)-2(a^2b-1)-2ab^2-2,其中a=-2,b=2
2(a^2+ab^2)-2(a^2b-1)-2ab^2-2=2(a^2+ab^2-a^2b+1-ab^2-1)
=2(a^2-a^2b)=2a^2(1-b)=2*4*(-1)=-8