Question

if sin theta =4/5 then find cot theta

Answer 1

sin Ф = 4/5

from figure, sin Ф =AB/AC

Let BC = x

According to Pythagoras theorem,

AC² = AB² + BC²

5² = 4² + x²

25 = 16 + x²

25 - 16 = x²

9 = x²

(Taking under square root on both sides)

∴ x = 3

∴ Cot Ф = BC /  AB = 3/4.