Please help me with this Problem

$\large Sin \theta+Sin^{2} \theta+Sin^{3} \theta=1$

Find the value of

$\large Cos^{6} \theta-4Cos^{4} \theta+8Cos^{2} \theta$

Thanks!!

#Algebra #Geometry #NumberTheory #Trigonometry

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`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`	$\sum_{i=1}^3$
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`\boxed{123}`	$\boxed{123}$

Comments

There's no "nice" solution. You can determine the value of $\cos^2\theta$ by squaring the first equation and solve the quartic equation, but the final value does not have a nice form.

Pi Han Goh - 5 years, 7 months ago

I'm sorry !I think the question was wrongly printed in my book!! I searched and found that its Cos^6theta-4Cos⁴+8Cos²!!

Thanks for your reply!

naitik sanghavi - 5 years, 7 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}`	$\boxed{123}$