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If P(n)=cos^(n)theta+sin^(n)theta and Q(...

If `P_(n)=cos^(n)theta+sin^(n)theta` and `Q_(n)=cos^(n)theta-sin^(n)theta` then show that `p_(n-2)=-sin^(2)theta cos^(2) theta p_(n-4)` hence show that
`p_(4)=1-2 sin^(2) theta cos^(2) theta`
`Q_(4)=cos^(2) theta- sin^(2) theta`

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MOTION-TRIGNOMETRIC RATIOS & IDENTITIES -Exercise -3
  1. Eliminate theta from the relations a sec theta=1-b tan theta,a^(2)sec^...

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  2. If (ax)/(cos theta)+(by)/(sin theta)=a^(2)-b^(2), (ax sin theta)/(cos^...

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  3. If P(n)=cos^(n)theta+sin^(n)theta and Q(n)=cos^(n)theta-sin^(n)theta t...

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  4. If tantheta=-5/12, theta is not in the second quadrant, then show tha...

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  5. यदि A + B=45^(@) सिद्ध कीजिए : (1+tan A ) .(1+tan B) =2

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  6. If sinx+siny=a and cos x+cosy =b then value of sin(x+y) =

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  7. If x+y+z=(pi)/(2) show that sin 2x + sin 2y + sin 2z =4 cos x cosy co...

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  8. If x+y=pi+z, then prove that sin^2x+sin^2y-sin^2z=2 sinx siny cos z.

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  9. A+B+C = 2S then prove that cos (S-A) + cos(S-B) + cos (S-C)+cos S=4 co...

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  10. If A+B+C =180^(@) then prove that sin 2A + sin 2B+ sin 2C = 4 sin A s...

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  11. If tan x=(3)/(4) " and " pi lt x lt .(3pi)/(2) find the value of ...

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  12. Prove taht {(1-cot^2((alpha-pi)/4))/(1+cot^2((alpha-pi)/4))+cos(alpha/...

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  13. 4(cos^3 2 0^(@)+cos^3 4 0^(@))=3(cos2 0^(@)+cos4 0^(@))

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  14. Prove that (i) (sec 8A -1)/(sec 4A -1) =(tan 8A)/(tan 2A) (ii) (c...

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  15. Prove that sin 3x .sin^(3) x+cos 3 x . Cos^(3)x=cos^(3) 2x

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  16. If tan beta=(tan alpha + tan gamma)/(1+ tan alpha . tan gamma) Prove...

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  17. Prove that sin^2 theta+sin^2 2theta+sin^2 3theta+....+sin^2 n theta=n/...

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  18. सिद्ध कीजिए कि - cos x+cos ((2pi)/(3)+x)+cos((2pi)/(3)-x)=0

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  19. Find the maximum and minimum values of (i) cos 2x + cos^(2)x (ii) ...

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  20. An maximum value of 1+4 sin theta + 3 cos theta is

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