Question

当x=2时,代数式(2p^3)(x^2)-(1/2p^2)x-20的值为140,问当x=1时,代数式(p^3)(x^3)

Answer 1

当x=2时候,(2p^3)(x^2)-(1/2p^2)x-20=140

8p^3-p^2=160

p^3-1/8p^2=20

当x=-1时候

（p^3)(x^3)+(1/8p^2)(x^4)-40

=-p^3+1/8p^2-40

=-（p^3-1/8p^2)-40

=-20-40

=-60