Question

[(x+2y)(x-2y)-(2x-y)²+(3x-y)(2x-5y)]÷(-1/2x)

怎么算哪！！谢谢大家啦

Answer 1

[(x+2y)(x-2y)-(2x-y)^2+(3x-y)(2x-5y)]÷(-1/2x)
=[(x^2-4y^2)-(4x^2+y^2-4xy)+(6x^2-17xy+5y^2)]÷(-1/2x)
=(3x^2-13xy)×(-2/x)
=26y-6x

Answer 2

原式=(x²-4y²-4x²+4xy-y²+6x²-17xy+10y²)×(-2x)
=(3x²-13xy+5y²)×(-2x)
=(3x²-13xy+5y²)×(-2x)
=3x²×(-2x)-13xy×(-2x)+5y²×(-2x)
=-6x³+26x²y-10xy²