Question

How do you simplify `\frac { x + 7} { x - 1} - \frac { x + 8} { x + 1}`?

Answer 1

`frac{x+15}{{x-1)(x+1)}`

Explanation:

Numerator `x^2 + 8x + 7 - x^2 - 7x + 8 = x + 15` using
`frac{a}{b}- frac{c}{d} = frac{ad-bc}{bd}`