Question

find the value of sin θ if cos θ = 3/5​

Answer 1

Answer:

Sin θ = 4/5

Step-by-step explanation:

cos θ = 3/5​ = B/H

By Pythagoras theorem:

H² = B² + P²

5² = 3² + P²

25 = 9 + P²

P² = 25 - 9

P² = 16

P = √16

P = 4

Sin θ = P/H

          = 4/5

Answer 2

Answer:

$\cos \alpha = \frac{3}{5} = \frac{base}{hypotenuse} \\ {hypotenuse}^{2} = {base}^{2} + {perpendicular}^{2} \\ perpendicular = \sqrt{ {hypotenuse}^{2} - {base}^{2} } \\ = \sqrt{ {5}^{2} - {3}^{2} } \\ = \sqrt{25 - 9} \\ = \sqrt{16 } \\ = 4 \\ \sin \alpha = \frac{perpendicular}{hypotenuse} \\ = \frac{4}{5}$