simplify (1/y+1/x)/(x/y-y/x)
Let's simplify: 1y + 1xxy -yx
ⓘ To add fractions, put them over the same denominator, then add the numerators: 1y + 1x = x + yyx, xy -yx = x·x -y·yyx
x + yyxx·x -y·yyx
ⓘ Multiplying powers with the same base adds the exponents: x·x = x2, y·y = y2
x + yyxx2 -y2yx
ⓘ Dividing is multiplying by the reciprocal: x + yyxx2 -y2yx = x + yyx·yxx2 -y2
x + yyx·yxx2 -y2
ⓘ To multiply fractions, multiply the numerators together and the denominators together: x + yyx·yxx2 -y2 = (x + y)·yxyx·(x2 -y2)
(x + y)·yxyx·(x2 -y2)
Using the formula: a2 -b2 = (a -b)·(a + b), we simplify the fraction: x + yx2 -y2 by the common factor: x + y to get the new fraction: 1x -y
▶Simplified form:   1x -y