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If A+B+C=(3pi)/2, t h e ncos2A+cos2B+cos...

If `A+B+C=(3pi)/2, t h e ncos2A+cos2B+cos2C` is equal to (a) `1-4cos Acos BcosC` (b) `4sinAsinBsinC` (c) `1+2cosAcosBcosC` (d) `1-4sinAsinBsinC`

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CENGAGE ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
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  2. The value of cos e cpi/(18)-4sin(7pi)/(18) is

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  3. If A+B+C=(3pi)/2, t h e ncos2A+cos2B+cos2C is equal to (a) 1-4cos Ac...

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  4. Prove that: (costheta)/(1+sintheta)=tan(pi/4-theta/2)

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  5. If A,B,C, are the angles of a triangle such that cot(A/2)=3tan(C/2), ...

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  6. The maximum value of cos^2(45^0+x)+(sinx-cosx)^2 is

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  7. Let alpha,betaa n dgamma be some angles in the first quadrant satisfyi...

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  8. If tanx=ntany ,n in R^+, then the maximum value of sec^2(x-y) is eq...

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  9. Prove that: (1+sintheta-costheta)/(1+sintheta+costheta)=tantheta/2

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  10. The greatest integer less than or equal to 1/(cos290^0)+1/(sqrt(3)sin2...

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  11. If alt=3cosx+5sin(x-pi/6)lt=b for all x then (a , b) is (a)(-sqrt(...

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  12. Prove that: (cos2theta)/(1+sin2theta)=tan(pi/4-theta)

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  13. If sin(x+20^0)=2sinxcos40^0,where in (0,pi/2), then which of the foll...

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  14. cosθ/ (1-tanθ) + sinθ/ (1−cotθ) is equals to ​

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  15. If x/(costheta)=y/(cos(theta-(2pi)/3))=z/(cos(theta+(2pi)/3)) then x...

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  16. Prove that : (cosecθ−cotθ)^2 = (1+cosθ)/(1−cosθ) ​

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  17. Let (sin(theta-alpha))/("sin"(theta-beta))=a/b a n d(cos(theta-alpha)...

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  18. (1+sin2theta+cos2theta)/(1+sin2theta-cos2theta)=?

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  19. The value of expression (2(sin1^0+sin2^0+sin3^0+...+sin89^0))/(2(cos1...

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  20. If sintheta1sintheta2-costheta1costheta2+1=0, then the value of tan((...

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