Question

4.
If A = 20° and E = 25°, then the value of
(1 + tan A) (1 + tan E) is
(1) V3
(2) 2
(3) 1+12
(4) 2(tanA + tanB)​

Answer 1

Answer:

Step-by-step explanation:

tan 45° = tan(20° + 25°)

        1   = (tan20° + tan25°) / (1 -  tan20° × tan25°)

1 -  tan20° × tan25° = tan20° + tan25° -----(1)

Now if we multiply (1 + tan20°) (1 + tan25°) =  1 + tan20° + tan25° + tan20° × tan25°

from eq (1) tan20° + tan25° + tan20° × tan25° = 1

hence 1 + 1 =2 option b is correct