Question

b) (1
+ tanA)2 + (1 - tanA)2 = 2 sec?A.​

Answer 1

Step-by-step explanation:

we have that:

(1+tanA)²+(1-tanA)²;

= 1+tan²A+2tanA+1+tan²A-2tanA;

=2+2tan²A

=2(1+tan²A)                     (∵sec²A=1+tan²A)

=2sec²A