x的3次方y的2次方加3x的2次方y的2次方加2分之1乘以y减1,其中x=2y=负的2分之1

2025-05-09 19:24:34
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回答1:

(X^3)(Y^2)+(3x^2)(Y^2)+(1/2)(Y-1)
=(y^2)(x^2)(x+3)+(1/2)[(-1/4)-1]
=(1/16)(1/4)(-1/2+3)+(1/2)(-5/4)
=(1/16)(1/4)(5/2)-(5/8)
=(1/16)(5/8)-(5/8)
=(5/8)(1/16-1)
=(5/8)(-15/16)
=-75/128