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If 2 cos theta= a+(1)/(a) and 2 cos phi=...

If `2 cos theta= a+(1)/(a) and 2 cos phi= b +(1)/(b)`, show that `2 cos (theta- phi) =(a)/(b)+(b)/(a)`

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CHHAYA PUBLICATION-MISCELLANEOUS EXAMPLES-TRIGONOMETRY
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  2. If angles alpha and beta satisfy the equation a cos theta+ b sin theta...

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  3. If sec alpha and "cosec" alpha are the roots of x^(2)- px+q=0 then sh...

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  4. If cot^(2) theta= cot (theta-alpha) cot( theta- beta), prove that cot...

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  5. If cos 2 A sin 2 B= cos 2 C sin 2D, prove that tan (C+A) tan (C-A) tan...

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  8. If tan^(2) alpha+ 2tan alpha tan 2 beta= tan^(2) beta+ 2 tan beta tan ...

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  11. If (tan (alpha- beta+ gamma))/(tan (alpha+ beta- gamma))=(tan beta)/( ...

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  12. If 0 lt alpha lt (pi)/(2), (pi)/(2) lt beta lt pi and cos alpha =(4)/(...

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  13. If alpha and beta be two roots of the equation a cos theta+ b sin thet...

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  15. If 2 sin A= sqrt(1+ sin 2A)- sqrt(1-sin2A) then find the limits of val...

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  17. In triangle ABC , if C is a right prove that (sin^(2)A)/(sin^(2)B)-(co...

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  18. Using the identity tan A =(sin 2A)/(1+cos2A) find the value of tan 15^...

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  19. Prove that the lengths of the chord of a circle which subtends an angl...

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