If a cos theta - b sin theta = c, find the value of a s... – Trigonometry

Trigonometryhard · Past Paper

If a cos theta - b sin theta = c, find the value of a sin theta + b cos theta.

Asqrt(a^2 + b^2 + c^2)

Bsqrt(a^2 + b^2 - c^2)

Ca + b - c

Dsqrt(c^2 - a^2 - b^2)

✓ Correct Answer: B — sqrt(a^2 + b^2 - c^2)

(a cos - b sin)^2 + (a sin + b cos)^2 = a^2 + b^2. So c^2 + x^2 = a^2 + b^2, x = sqrt(a^2 + b^2 - c^2).

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