Question

Is the sqrt of 1 - sin^2 theta = cos theta true? If so, in which quadrants does angle theta terminate?

Answer 1

Answer:

Answer: The answer is option B.

Step-by-step explanation:

Here,

We have,

${ \sin }^{2} theta \: + {cos}^{2}theta = 1$

${cos}^{2} \: theta = 1 - {sin}^{2} \: theta$

$cos \: theta = \sqrt{1 - { \sin }^{2}theta }$

So, it's true; and it lies in quadrant 1 and 4.

The reason according to the "CAST" rule cos theta is in 1st and 3rd quadrant cos theta is positive.