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Prove that 2sin2^0+4sin4^0+6"sin"6^0+......

Prove that `2sin2^0+4sin4^0+6"sin"6^0+.......+180sin180^0=90cot1^0dot`

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CENGAGE ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
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  3. Prove that 2sin2^0+4sin4^0+6"sin"6^0+.......+180sin180^0=90cot1^0dot

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  4. If A+B+C=180^@, then prove thatcos^2 A + cos^2 B +cos^2 C=1-2cosA cosB...

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  12. If u=sqrt(a^2 cos^2 theta + b^2sin^2theta)+sqrt(a^2 sin^2 theta + b^2 ...

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