Question

If sin Ɵ = 4 / 5, find cos Ɵ​

Answer 1

Answer:

I have explained it in the pic attached. hope it helps.

Answer 2

Step-by-step explanation:

We know that,

sin²Ɵ+cos²Ɵ=1

Therefore,

$({ \frac{4}{5} })^{2} + {cos}^{2}Ɵ = 1$

$\frac{16}{25} + {cos}^{2} Ɵ = 1$

${cos}^{2} Ɵ = 1 - \frac{16}{25}$

${cos}^{2} Ɵ = \frac{25 - 16}{25}$

${cos}^{2} Ɵ = \frac{9}{25}$