Trigonometry Help Needed

$If\quad cosp\theta +cosq\theta =0,\\ Prove\quad that\quad the\quad different\quad values\quad of\quad \theta \quad form\quad \\ two\quad arithmetical\quad progressions\quad in\quad which\quad the\quad \\ common\quad differences\quad are\quad \frac { 2\pi }{ p+q } and\quad \frac { 2\pi }{ p-q }$

#Geometry #Trigonometry #HelpMe!

Easy Math Editor

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
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Comments

bro @Rishi Sharma if you take 1 term to other side , you will find that the values of p and q are such adjusted that p and q lie in 1,4 quadrant or 2,3, quadrant a little simplification can give your answer easily ! :) got it ?

A Former Brilliant Member - 4 years, 6 months ago

Thanks @shubham dhull. I almost forgot that I ever wrote this note.

Rishi Sharma - 4 years, 6 months ago

no problem , happy to help !

A Former Brilliant Member - 4 years, 6 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$