Question

若(2x-y)/(x+2y)=5,则(12x-6y)/(x+2y)-(x+2y)/(2x-y)代数式的值为______.

Answer 1

(2x-y)/(x+2y)=5,等式两边乘以6,可得(12x-6y)/(x+2y)=30,(x+2y)/(2x-y)=1/5（倒数）,所以(12x-6y)/(x+2y)-(x+2y)/(2x-y)=30-1/5=149/5