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Show that (1+ cos. (pi)/(8))(1+cos. (3pi...

Show that `(1+ cos. (pi)/(8))(1+cos. (3pi)/(8))(1+ cos. (5pi)/(8))(1+ cos .(7pi)/(8))=(1)/(8)`

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The correct Answer is:
`=(1)/(8)=R.H.S`
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SRISIRI PUBLICATION-TRIGONOMETRIC RATIONS, TRANSFORMATIONS-VSAQ
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  3. Find the extreme values of 3sin^(2)x+5cos^(2)x.

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  4. In Delta Prove that tan A+tan B+ tan C =tan A tan B tan C.

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  5. If A+B+C= pi//2 then show that cot A + cot B+ cot C=cot A cot B cot C

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  6. If A+B=45^(@), then prove that (i) (1+ tan A) (1+ tan B) =2 (ii) (cot...

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  7. If A is not an integral multiple of (pi)/(2), prove that (i) tan A +...

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  8. Prove that sin ^(2) theta + sin ^(2) (theta+(pi)/(3))+ sin ^(2) (theta...

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  9. If tan alpha - tan beta =m and cot alpha - cot beta =n, then prove tha...

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  10. If (sin(alpha+beta))/(sin(alpha-beta)) = (a+b)/(a-b), then prove that ...

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  11. Prove that (1- sec 8 alpha )/(1- sec 4 alpha )=(tan 8 alpha )/( tan 2 ...

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  12. If tan theta . =(b)/(a) then prove that acos 2 theta +b sin 2 theta =a

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  13. Show that sin A= (sin 3A) /(1+2 cos 2A). Hence find the value of sin 1...

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  18. Prove that tan 9 ^(@) - tan 27 ^(@)- cot 27 ^(@) + cot 9^(@)=4

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  20. Show that (1+ cos. (pi)/(8))(1+cos. (3pi)/(8))(1+ cos. (5pi)/(8))(1+ c...

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