Question

先化简,再求值A-B分之B乘以B的平方分之A的立方加AB的平方-2A的平方B除以AB加B的平

Answer 1

B / (A-B) * (A^3+AB^2-2A^2B) / B^2 ÷ (B^2-A^2) / (AB+B^2) * (-B)^2 / A

= B / (A-B) * A (A^2+B^2-2AB) / B^2 * (AB+B^2) / (B^2-A^2) * (B)^2 / A

= B / (A-B) * A (A-B)^2 / B^2 * B(A+B) / [-(A+B)(A-B)] * (B)^2 / A

= B / (A-B) * A (A-B)^2 / B^2 * B(A+B) / [-(A+B)(A-B)] * (B)^2 / A

= - { B * A (A-B)^2 * B(A+B) * (B)^2 } / { (A-B) * B^2 * (A+B)(A-B) * A }

= - { AB^4 (A+B) (A-B)^2 } / { A B^2(A+B)(A-B)^2 }

= - B^2

= - (-3)^2

= - 9