Home
Class 11
MATHS
prove that cos(A+B)=cosAcosB-sinAsinB...

prove that `cos(A+B)=cosAcosB-sinAsinB`

Text Solution

Verified by Experts

The correct Answer is:
`cos2x=cos^(2)x-sin^(2)x`.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • ANNUAL EXAMINATION QUESTION PAPER - 1

    SUBHASH PUBLICATION|Exercise SECTION -D|10 Videos

  • ANNUAL EXAMINATION QUESTION PAPER - 2017 (NORTH) (WITH ANSWERS)

    SUBHASH PUBLICATION|Exercise Part - E (V.Answer any One question:)|4 Videos

Similar Questions

Explore conceptually related problems

cos(A-B)=cosAcosB+sinA sinB

Prove Geometrically cos(x+y)=cosx,cosy-sinx.siny and hence prove that cos(x-y)= cosxcosy+sinxsiny using unit circle concept ?

Prove geometrically that cos (x+y)= cosx.cosy- sinx.siny and hence show that cos2x=cos^2x-sin^2x .

Prove that geometrically that cos (x+y)= cosx.cosy-sinx.siny and hence show that cos2x=cos^2x-sin^2x .

Prove geometrically that cos(x + y) = cos x cos y - sinx sin y and hence prove cos((pi)/(2) + x) = - sin x .

Prove that cos 3x=4 cos ^3x-3cos x

Prove that cos^(2)2x-cos^(2)6x=sin4x.sin8x ?

Prove that: cos3x=4cos^(3)x-3cosx

If B= 15^(@) ,then prove that 4 sin 2B.cos 4B.sin6B=1.

Prove that (cos7x+cos5x)/(sin7x-sin5x)= cotx ?

Home
Profile