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Prove that: 2cos frac (pi)(13)cos frac (...

Prove that: `2cos frac (pi)(13)cos frac (9pi)(13)+cos frac (3pi)(13)+cos frac (5pi)(13)=0`

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Prove that : 16 cos frac (2pi)(15) cos frac (4pi)(15) cos frac (8pi)(15) cos frac (16pi)(15) =1.

Prove that sin frac (pi)(14) sin frac (3 pi)(14) sin frac (5pi)(14) sin frac (7pi)(14)=1/8 .

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

Prove that : 3 sin frac (pi)(6) sec frac (pi)(3)-4 sin frac (5pi)(6) cot frac(pi)(4)=1 .

Prove that : (1+cos frac (pi)(8)) (1+cos frac (3pi)(8)) (1+cos frac (5pi)(8)) (1+cos frac (7pi)(8))=1/8 .

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

Prove that: 2sin^2frac (pi)(6)+cosec^2frac (7pi)(6)cos^2frac (pi)(3)=3/2

The value of : (1+cos frac (pi)(6)) (1+cos frac (pi)(3))(1+cos frac (2pi)(3)) (1+cos frac (7pi)(6)) is:

In any triangle ABC, prove that : cos frac (A)(2) +cos frac (B)(2)+cos frac (C)(2)= 4 cos frac (pi-A)(4) cos frac (pi-B)(4) cos frac (pi-C)(4) .

Prove that: 2sin^2frac (3pi)(4)+2cos^2frac(pi)(4)+2sec^2frac (pi)(3)=10

JBD PUBLICATION-MODEL PAPER (2)-EXERCISE
  1. In a survey of 600 students in a school, 150 students were found to be...

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  2. The relation 'f' is defined by f(x)={(x^2,0lexle3), (3x, 3lexle10):} ...

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  3. Prove that: 2cos frac (pi)(13)cos frac (9pi)(13)+cos frac (3pi)(13)+co...

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  4. If sinx=-5/13 and x lies in IIIrd quadrant. Find the value of secx+tan...

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  5. Using mathematical induction , show that n(n+1)(n+5) is a multiple of...

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  6. Determine the number of 5 card combinations out of a deck of 52 cards ...

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  7. If 1/(6!)+1/(7!)=x/(8!), find x

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  8. Find the sum of all natural numbers lying between 100 and 1000, which ...

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  9. Find the sum of n terms of the following sequences: 8+88+888+……………..up...

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  10. Find the angle between x-axis and line joining points (5,-1) and (3,-4...

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  11. Find the equation of the circle with the centre (1/2,1/4) and radius 1...

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  12. Evaluate: underset(xrarr1)lim[(x-2)/(x^2-x)-1/(x^3-3x^2+2x)].

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  13. Find the derivative of 5x^3(x-1).

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  14. Three coins are tossed once. Find the probability of getting at least ...

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  15. Three coins are tossed once. Find the probability of getting at most t...

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  16. If (5-3i)^2=a+ib then find the values of a and b.

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  17. If x-iy= sqrt((a-ib)/(c-id)) prove that (x^2+y^2)^2= (a^2+b^2)/(c^2+d^...

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  18. Solve the following system of inequalities graphically: 2x + y ge 6, 3...

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  19. Solve the system of inequalities and show that solution graphically on...

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  20. Evaluate: underset(xrarr2)lim (x^3-4x^2+4x)/(x^2-4).

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