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Given that cos (A + B) = cos A cos B-sin...

Given that cos (A + B) = cos A cos B-sin A sin B. Find the value of cos `105^@`.

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MBD-INTRODUCTION TO TRIGONOMETRY-EXERCISE
  1. If 3tan2theta=sqrt3 find theta .

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  2. Find x , if 2cosec^2 30^@+xsin^2 60^@-3/4 tan^2 30^@ = 10 .

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  3. Given that cos (A + B) = cos A cos B-sin A sin B. Find the value of co...

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  4. Find x if :- cos(10^@+x)=1/2 .

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  5. Find x if :- tan(40^@+x)=sqrt3 .

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  6. Find x if :- sin(20^@+x)=cos60^@ .

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  7. Find x if :- if cos (40+x)=sin30^@. Find the value of x.

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  8. Show that :- 2[cos^4 60^@+sin^4 30^@]-[tan^2 60^@+cot^2 45^@]+3sec^2 ...

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  9. Show that :- 2[cos^2 45^@+tan^2 60^@]-6[sin^2 45^@-tan^2 30^@]=6 .

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  10. Find the value theta in the following :- 2sin2theta=sqrt3 .

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  11. Find the value theta in the following :- 2cos3theta=1 .

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  12. Find the value theta in the following :- sqrt3 tan2theta-3=0 .

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  13. Find the value theta in the following :- tan3theta=sin45^@ cos45^@+sin...

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  14. Find the value theta in the following :- costheta=cos60^@ cos30^@ +sin...

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  15. Find the value theta in the following :- sin2theta=sin60^@cos30^@-cos...

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  16. Ifsin(A-B)= sin A cosB-cos A sin B and cos(A-B) = cosA cosB + sin A si...

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  17. Express cot 85^@ + cos 75^@ in terms of trigonometric ratios of angles...

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  18. Without using Trigonometric tables, evaluate:- 2(sin43^@)/(cos47^@)-(c...

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  19. Without using Trigonometric tables, evaluate:- (cos^2 20^@+cos^2 70^@)...

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  20. Without using Trigonometric tables, evaluate:- 2(cos67^@)/(sin23^@)-(t...

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