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If A-B=60^(@) then cos^(2)A+cos^(2)B-cos...

If `A-B=60^(@)` then `cos^(2)A+cos^(2)B-cosA cosB=`

A

`1/4`

B

`3/4`

C

`5/4`

D

`1/2`

Text Solution

Verified by Experts

The correct Answer is:
B
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AAKASH SERIES-MULTIPLE & SUBMULTIPLE ANGLES-PRACTICE EXERCISE
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  3. If A-B=60^(@) then cos^(2)A+cos^(2)B-cosA cosB=

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  4. (Sin^(3)43^(@)-Sin^(3)17^(@))/(Sin43^(@)-Sin17^(@))=

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  13. IF tan^2 theta=2 tan^2 phi +1 then find the value of cos 2 theta+sin^2...

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  15. If (sin alpha )/(a) = ( cos alpha )/(b) , then a sin 2alpha + b cos 2...

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