Question

 Представьте в виде дроби

Answer 1

$frac{3x-1}{x^2} - frac{x-9}{3x} = frac{3(3x-1)-x(x-9)}{3x^2} = frac{9x-3-x^2+9x}{3x^2} = frac{-x^2+18x-3}{3x^2} =-frac{x^2-18x+3}{3x^2}$


$frac{1}{2a-b} - frac{1}{2a+b} = frac{(2a+b)-(2a-b)}{(2a-b)(2a+b)} = frac{2a+b-2a+b}{4a^2+2ab-2ab-b^2} =frac{2b}{4a^2-b^2}$


$frac{5}{c+3} - frac{5c-2}{c^2+3c} = frac{5}{c+3} - frac{5c-2}{c(c+3)} = frac{5c-(5c-2)}{c(c+3)} =frac{5c-5c+2}{c(c+3)} =frac{2}{c^2+3c}$