x的平方-4分之x的平方-2x除以(x-2-x+2分之2x-4)其中x=6

问题描述:

x的平方-4分之x的平方-2x除以(x-2-x+2分之2x-4)其中x=6

数学之美团为你解答
(x²-2x)/(x²-4) ÷ [ x-2 - (2x-4)/(x+2)]
= x(x-2)/[(x+2)(x-2)] ÷ [ (x²-4)/(x+2) - (2x-4)/(x+2)]
= x/(x+2) ÷ (x²-2x)/(x+2)
= x/(x+2) * (x+2)/ x(x-2)
= 1/(x-2)
= 1/4