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If acos2theta+bsin2theta= c, alpha and b...

If `acos2theta+bsin2theta= c, alpha and beta` as its roots , then prove that `tanalpha+t a nbeta=(2 b)/(a+c)`, `tanalpha*t a nbeta=(c-a)/(c+a)` , `tan(alpha+beta)=b/a`

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To prove the given equations based on the equation \( a \cos 2\theta + b \sin 2\theta = c \) where \( \alpha \) and \( \beta \) are its roots, we will follow these steps: ### Step 1: Rewrite the equation in terms of tangent We start with the equation: \[ a \cos 2\theta + b \sin 2\theta = c \] Using the identities \( \cos 2\theta = \frac{1 - \tan^2 \theta}{1 + \tan^2 \theta} \) and \( \sin 2\theta = \frac{2 \tan \theta}{1 + \tan^2 \theta} \), we can rewrite the equation as: ...
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RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS OF MULTIPLE AND SUBMULTIPLE ANGLES-All Questions
  1. If tanA=1/7a n d tanB=1/3 , show that cos2A=sin4Bdot

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  2. If 2t a nalpha/2=tan(beta/2) , prove that cosalpha=(3+5cosbeta)/(5+3c...

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  3. If acos2theta+bsin2theta= c, alpha and beta as its roots , then prove ...

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  4. If cosalpha+cosbeta=0=s inalpha+s inbeta, then prove that cos2alpha+co...

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  5. Prove that: 15sin(5pi)/(12)+15cos(5pi)/(12)-20sin^3(5pi)/(12)-20cos(5p...

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  6. Prove that: sin(pi/5)sin( (2pi)/5)sin(3pi/5)sin(4pi/5)=5/(16)

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  7. Find general solution of the trigonometric equation sin5theta =1

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  8. Prove that: sin^4(pi/8)+sin^4((3pi)/8)+sin^4((5pi)/8)+sin^4((7pi)/8)=...

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  9. Prove that: cos^4pi/8+cos^4(3pi)/8+cos^4(5pi)/8+cos^4(7pi)/8=3/2

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  10. Prove that:tan6^0tan42^0tan66^0tan78^0=1.

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  11. If tanalpha=(1-cosbeta)/(sinbeta),t h e n (a)tan3alpha=tan2beta (b) ...

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  12. Prove that: sin36^0=(sqrt(10-2sqrt(5)))/4 .

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  13. The value of (cos3theta)/(2cos2theta-1) is equal to (a) costheta (b) ...

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  14. The value of cos^4theta+sin^4theta-6cos^2theta is (a) cos2theta (b) s...

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  15. Prove that: sin(pi/10)+sin((13pi)/10)=-1/2

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  16. If tan(pi//4+theta)+""tan(pi//4-theta)=lambdasec2theta,t h e nlambda= ...

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  17. Prove that: (1+cos4x)/(cot x-tanx)=1/2sin4x

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  18. Prove that: (cos7x-cos8x)/(1+2cos5x)=cos2x-cos3x

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  19. To prove (cos5x+cos4x)/(1-2cos3x)=-cos2x-cosx

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  20. If tantheta= t, then tan2theta+sec2theta is equal to (a) (1+t)...

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