Home
Class 12
MATHS
For for A=133^(@),2cos""A/2is equal to...

For `for A=133^(@),2cos""A/2`is equal to

A

`-sqrt(1+sin A)-sqrt(1-sin A)`

B

`-sqrt(1+sin A)+sqrt(1-sin A)`

C

`sqrt(1+sin A)-sqrt(1-sin A)`

D

`sqrt(1+sin A)+sqrt(1-sin A)`

Text Solution

Verified by Experts

The correct Answer is:
C
For `A=133^@, A/2=66.5^(@) rArr sin""A/2 gt cos ""A/2 gt0`
Hence, `sqrt(1+sin A)=sin""A/2+cos""A/2 .....(1)`
and `sqrt(1-sin A)=sin""A/2-cos""A/2 .......(ii)`
Subtract (ii) from (i), `2cos""A/2=sqrt(1+sin A)-sqrt(1-sin A)`
Promotional Banner

Similar Questions

Explore conceptually related problems

If A=111^(@), then 2cos((A)/(2)) is equal to

1+ cos ^(2) 2A is equal to

2 cos x cos y is equal to:

cos((pi)/(2)+x) is equal to:

cos((pi)/(2)+x) is equal to:

In a DeltaABC ,a cos^(2)B/2+bcos^(2)A/2 is equal to

cot ^(2) A - cos ^(2) A is equal to :

cos 2 theta is not equal to

cos 1^(@) + cos2^(@) + cos 3^(@) + ….+cos 180^(@) is equal to

In a DeltaABC, b cos^(2) C/2 + c cos^(2) B/2 is equal to