Question

The angle e lies in Quadrant II.
sin 0 = 3/4
What is cos O?​

Answer 1

-√7/4

Explanation:

Mathematically;

Sine is the ratio of opposite to hypotenuse

So here, hypotenuse is 4

The opposite is 3

To get the adjacent, we use the Pythagoras’ theorem which states that the square of the hypotenuse is equal the sum of the squares of the two other sides

Let the adjacent be x

4^2 = 3^2 + x^2

x^2 = 16-9

x^2 = 7

x = √7

The cosine is the ratio of the adjacent to the hypotenuse

Since we want to consider quadrant II

Cosine is negative here;

So the answer for Cos will be;

Cos theta = -√7/4