If `B+C=60^(@)` then show that : `sin(120^(@)-B)=sin(120^(@)-C)`

(i) If x=(11pi)/(4) , prove that: "sin"^(2)x-cos^(2)x+2"tan"x-sec^(2)x=-4 . (ii) If 8 theta=pi , prove that cos theta+cos7theta=0 (iii)If B+C= 60^(@) , show that: "sin"(120^(@)-B)="sin"(120^(@)-C) .

If B + C = 60^@ , show that : sin (120^@- B) = sin (120^@ -C) .

If theta+phi=60^@ ,then show that sin(120^@-theta)=cos(30^@-phi)

If theta + phi = 60^(@) , show that, sin (120^(@) - theta) = cos (30^(@) - phi) .

sin theta+sin(120^(@)+theta)-sin(120^(@)-theta

Time period of sin x sin(120^(@)-x)sin(120^(@)+x)=

The period of sin x sin(120^(@) + x) sin(120^(@) -x) is

If A+B+C= 180^(@) , then show that sin 2A+ sin 2B+ sin 2C =4 sin A sin B sin C .

If A+B+C=270^(@) then show that sin2A+sin2B-sin2C=-4sinAsinBcosC

Assertion (A):cos^(2)theta+cos^(2)(60^(@)-theta)+cos^(2)(60^(@)+theta)=(3)/(2)sin alpha-sin(120^(@)-alpha)+sin(120^(@)+alpha)=0