Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Trigonometry

Question:

If a sinA + b cosA = c, then a cosA - b sinA is equal to:

Options:

$\sqrt{a^2-b^2-c^2}$

$\sqrt{a^2+b^2-c^2}$

$\sqrt{a^2+b^2+c^2}$

$\sqrt{a^2-b^2+c^2}$

Correct Answer:

$\sqrt{a^2+b^2-c^2}$

Explanation:

Given :-

a sinA + b cosA = c

We know,

If a sinθ + b cosθ = c

Then , a cosθ - b sinθ = $\sqrt{a^2+b^2-c^2}$

Similarly,

a cosA - b sinA

= $\sqrt{a^2+b^2-c^2}$