# Trig Doubt

Question 18: If $$\tan \theta = \frac ab$$, show that $$\frac{a \sin \theta - b \cos \theta}{a \sin \theta + b\cos \theta} = \frac{a^2-b^2}{a^2+b^2}$$.

Note by Swapnil Das
3 years ago

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Just divide the numerator and denominator of the LHS by $$\tan\theta$$

- 3 years ago

Thank you for helping!

- 3 years ago

No problem

- 3 years ago

Comment deleted Jun 14, 2015

RD Sharma- 11

- 3 years ago

Use componendo dividendo

- 3 years ago

Whoever edited it, Thanks!

- 3 years ago