Simplify( 1/a-b)+(4/b-/a+-5b/b^2-a^2)1. 02.-10b3.-14a+18b 

The answer is 0.    move the denominators so that the a term is always first    factor a² - b² into (a-b)(a+b)    can add the numerators of fractions with common denominators    to add these fractions, we need a common denominator for all of them.multiply the numerator and denominator of -3/(a-b) by (a+b)multiply the numerator and denomintaor of 8/(a+b) by (a-b)    they all have the same denominators since (a+b)(a-b) is the same as (a-b)(a+b). so we can add/subtract all of their numerators and then just combine like terms.