A trigonometry problem! NEED HELP!!

Prove that

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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}`	$\boxed{123}$

Comments

Please someone prove this

Ashley Shamidha - 6 years, 2 months ago

What are the the restrictions on B and C?

Akshay Bodhare - 6 years, 2 months ago

ABC is a triangle and A+B+C =180

Ashley Shamidha - 6 years, 2 months ago

@Ashley Shamidha – Then expand to get $\tan A (\tan B+\tan C) + \tan B \tan C$ .

It's easy to prove $\frac{\sin A} {\cos B \cos C}=\tan B + \tan C$

Then after some simplification,you will get the required expression as, $1+\sec A \sec B \sec C$ , which is always greater than 2 in case of triangle.

Akshay Bodhare - 6 years, 2 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}`	$\boxed{123}$