Question

已知Y=X平方-2X+1/X平方-1除以X平方-X/X+1乘以5x试说明在代数式有意义的情况下,不论x取何值y的值都不变

Answer 1

y=[(x^2-2x+1)/(x^2-1)]÷[(x^2-x)/(x+1)]*5x

=[(x-1)^2/(x-1)(x+1)]÷[x(x-1)/(x+1)]*5x

=[(x-1)/(x+1)]÷[x(x-1)/(x+1)]*5x

=(1÷x)*5x

=5

你能明白,赞同