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Prove thatcos^2alpha+cos^2(120^@-alpha)+...

Prove that`cos^2alpha+cos^2(120^@-alpha)+cos^2(120^@+alpha)=3/2`

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Prove that cos alpha cos (120^(@) + alpha) cos (240^(@) + alpha) = 1/4 cos 3 alpha

Prove that, cos alpha + cos(120^(@) + alpha) + cos (120^(@) - alpha) = 0

Show that, cos^(2)alpha + cos^(2) (120^(@) - alpha) + cos^(2) (120^(@) + alpha) = 3/2.

Prove that : sec alpha+ sec (120^(@)+ alpha) sec (120^(@)-alpha)=-3 sec 3 alpha

Prove that, cos^(3) alpha + cos^(3) (120^(@) + alpha) + cos^(3) (240^(@) + alpha) = 3/4 cos 3 alpha

Prove that sin alpha + sin (120^(@) + alpha) + sin(240^(@)+ alpha)=0

Prove that, sin^(2) alpha + sin^(2) (120^(@) - alpha) + sin^(2) (120^(@) + alpha) = 3/2

If alpha= (2pi)/(7) , then prove that cos alpha+ cos 2 alpha+ cos 4alpha=-(1)/(2) . Hence, deduce that sin alpha+ sin 2alpha+ sin 4alpha=(sqrt(7))/(2)

Prove that, (1+ cos 2 alpha + sin 2 alpha)/(1-cos 2 alpha +sin 2 alpha)=cot alpha

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UNITED BOOK HOUSE-THE SCOTTISH CHURCH COLLEGIATE SCHOOL-EXERCISE
  1. Find equations of all possible circles that touch the y axis at the po...

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  2. Find the equation of the circles which touche the y axes id and passes...

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  3. Show that lim(xrarr1)(1-x)tan((pix)/2)=2/pi

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  4. If 2f(x)+3f(-x)=x^2-x-1,then find f'(1).

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  5. Find from the first principle,the derivative of tan 2x at x=pi/8

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  6. If f(x) is differentiable at x=a then show that lim(xrarr0)(x^2f(a)-a^...

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  7. Prove the following by contradiciton ."The sum of a rational and an ir...

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  8. Let a statement p:/\ABCis right angle triangle,and another statement q...

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  9. Let a statement p:/\ABCis right angle triangle,and another statement q...

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  10. Let a statement p:/\ABCis right angle triangle,and another statement q...

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  11. Let a statement p:/\ABCis right angle triangle,and another statement q...

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  12. Find the range of the function f(x)=1/(3sinx+4cosx+6)

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  13. Prove thatcos^2alpha+cos^2(120^@-alpha)+cos^2(120^@+alpha)=3/2

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  14. Let f(x)=4^x/(4^x+2)prove.that f(x) + f(1- x)= 1. Hence prove that f(1...

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  15. Ifx+iy=3/(2+costheta+i sintheta)then show that x^2 + y^2 = 4x - 3.

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  16. If S be the sum. P be the product,and R the sum of the reciprocals of ...

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  17. If the equation x^2+px+qr=0and x^2+qx+pr=0(p!=q,r!=0)has same root the...

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  18. If n>1 be a +ve integer,then using binomial theorm show that (4^(2n+2)...

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  19. The equation of the axis and directrix of a parabola are y-3=0 and ...

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  20. If l and l' be the lengths of the segment bar(PS) and bar(P'S) of a fo...

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