Question

If Sin theta=3/4,find the value of cos theta

Answer 1

`Cos \ \theta = (√(7) )/(4)`

Explanation:

Given;

Sin θ = 3/4

To calculated Cos θ;

make a sketch of right-angled triangle with following sides;

opposite side = 3

hypotenuse side = 4

then, the adjacent side will be calculated from Pythagoras theorem;

let the adjacent side = b

b² = 4² - 3²

b² = 16 - 9

b² = 7

b = √7

Therefore, Cos θ is now calculated as;

Cos θ = adjacent / hypotenuse

Cos θ = √7/4

`Cos \ \theta = (√(7) )/(4)`

Therefore,
`Cos \ \theta = (√(7) )/(4)`