若n为正整数,且x的2n次方=5,求(3乘2x的3n次方)的2次方一40(x的2次方)的2n次的

2025-02-24 13:11:01
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回答1:

x^2n=5 (3*2x^3n)^2-40(x^2)^2n=3^2*(x^2n)^3-40*(x^2n)^2=9*5^3-40*5^2=9*5^3-8*5^3=5^3=125