Question

simplifique: a^-1 - b^-1 sob a^-1+ b^-1
2) (x^-1+ y^-1) (x+y)

Answer 1

(a^-1)-(b^-1)
_________=
(a^-1)+(b^-1)

1/a-1/b
_______=
1/a+1/b

(b-a)/ab
_______=
(b+a)/ab

(b-a)/ab. x. ab /(b+a)
b-a/b+a

2) (x^-1+ y^-1) (x+y)
(1/x+1/y)(x+y)
x/x +y/x +x/y +y/y
1+y/x + x/y +1
y/x +x/y +2