Home
Class 11
MATHS
Prove the following: (i) "sin" alpha+...

Prove the following:
(i) `"sin" alpha+"sin"(alpha+(2pi)/(3))+"sin"(alpha+(4pi)/(3))=0`
(ii) `cos A+cos(120^(@)-A)+cos(120^(@)+A)=0`.

Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise Exercise 3( f)Long Answer type Question-II|2 Videos

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise Exercise 3(g)Short Answer type Question|4 Videos

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise Exercise 3( f)Short Answer type Question|5 Videos

  • STRAIGHT LINES

    MODERN PUBLICATION|Exercise Chapter test|12 Videos

Similar Questions

Explore conceptually related problems

Show that 4sin alpha*sin(alpha+(pi)/(3))sin(alpha+2(pi)/(3))=sin3 alpha

prove that 4sin alpha*sin(alpha+(pi)/(3))*sin(alpha+(2 pi)/(3))=sin3 alpha

cos alpha+cos(120^(@)+alpha)+cos(120^(@)-alpha)=0

Prove that: int_(0)^( pi)(x)/(1-cos alpha sin x)dx=(pi(pi-alpha))/(sin alpha)

sin alpha-sin2 alpha+sin3 alpha=4cos(3 alpha)/(2)cos alpha sin(alpha)/(2)

(1)/(sin3alpha)[sin^(3)alpha+sin^(3)((2pi)/(3)+alpha)+sin^(3)((4pi)/(3)+alpha)] is equal to

If sin alpha =(1)/(2) , prove that (3 cos alpha - 4 cos ^(3) alpha )=0.

The value of (sin(pi-alpha))/(sin alpha-cos alpha tan.(alpha)/(2))-cos alpha is

If sin alpha = (-3)/(5), where pi lt alpha lt (3pi)/(2), then cos ((alpha)/(2))=

Prove that sin^(3)alpha+sin^(3)(120^(@)+alpha)+sin^(3)(240^(@)+alpha)=-(3)/(4)sin3 alpha