Answer:
√7 / 4
Step-by-step explanation:
Trigonometrical identity are used to show the relationship between the sides and angles of a right angled triangle. Some trigonometric identities are:
sinΘ = opposite / hypotenuse, cosΘ = adjacent / hypotenuse, tanΘ = opposite / adjacent.
Given that cosΘ = 3 / 4
Therefore, cosΘ = adjacent / hypotenuse = 3 / 4
adjacent = 3, hypotenuse = 4. Let x be the opposite side, to get the opposite side, we use Pythagoras theorem:
opposite² + adjacent² = hypotenuse²
x² + 3² = 4²
x² + 9 = 16
x² = 7
x = √7
sinΘ = opposite/hypotenuse = √7 / 4
