Home
Class 11
MATHS
sin(pi/10)sin((3pi)/10)=............ A) ...

`sin(pi/10)sin((3pi)/10)=`............ A) `1/2` B) `(-1)/(2)` C) `(1)/(4)` D) `1`

A

`1/2`

B

`(-1)/(2)`

C

`(1)/(4)`

D

1

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Similar Questions

Explore conceptually related problems

cos(pi/7)cos((2pi)/7)cos((4pi)/7)= ................ A) 0 B) 1/2 C) 1/4 D) -1/8

2cos ""(pi)/(13)cos""(9pi)/(13)+cos""(3pi)/(13)+cos""(5pi)/(13)= ................ A) -1 B) 0 C) 1 D) 1/2

The value of sin ""31/3pi is .............. A) (sqrt3)/(2) B) (1)/(sqrt2) C) (-sqrt3)/(2) D) (-1)/(sqrt2)

If sintheta=(12)/(13),(0ltthetalt(pi)/(2))and cosphi=-(3)/(5),(piltphilt(3pi)/(2)) . Then , sin(theta+phi) will be................ A) (-56)/(61) B) (-56)/(65) C) (1)/(65) D) -56

If sin alpha = (-3)/(5), where pi lt alpha lt (3pi)/(2), then cos ((alpha)/(2))= ................ A) (-1)/( sqrt10) B) (1)/(sqrt10) C) (3)/(sqrt10) D) (-3)/(sqrt10)

The sum of the series sum _(n=1) ^(oo) sin ((n!pi)/(720)) is .............. A) sin ((pi)/(180)) + sin ((pi)/(360)) + sin ((pi)/(540)) B) sin ((pi)/(6)) +sin ((pi)/(30)) + sin ((pi)/(120)) + sin ((pi)/(360)) C) sin ((pi)/(6)) + sin ((pi)/(30)) + sin ((pi)/(120)) + sin ((pi)/(360))+sin ((pi)/(720)) D) sin ((pi)/(180))+ sin ((pi)/(360))

IF 2 sin ( theta +(pi)/(3)) = cos (theta -(pi)/(6)), then tan theta = ............... A) sqrt3 B) -(1)/(sqrt3) C) (1)/(sqrt3) D) -sqrt3

Maximum value of sin^4 theta + cos^4 theta is .............. A) 2 B) (1)/(2) C) -1 D) 1

The expression cos ((10pi)/13)+cos ((8pi)/13)+cos ((3pi)/13)+cos ((5pi)/13) is equal to............... A) -1 B) 0 C) 1 D) None of these

sin 10^(@) + sin 20^(@) + sin30^(@) +…+ sin 360^(@) is equal to................ A) 0 B) 1 C) -1 D) 1/2