Question

prove that tan70-tan25-tan70 multiplied by tan25=1

Answer 1

Hi
we know that

tan(a-b)=tana-tanb/1+tana*tanb

now
tan45=1=tan(70-25)


open it like above formula

1=tan70-tan25/1+tan70tan25

1+tan70tan25=tan70-tan25



in ur question
tan70-tan25-tan70tan25

use above equation in this equation
put value of

tan70-tan25
we get

1+tan70tan25-tan70tan25=1

hence proof
hope u
got it