1) Cos40°Cos30°+Sin40°Sin60°
2)sin150°Cos160°+Cos150°sin30°
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you can solve with the help of formula
sin (a+b) = sin a. CoS b + cos a. Sin b
CoS ( a-b) = cos a . CoS b + SIN a . Sin b
1) CoS 40 . CoS (90-60) + SIN 40 . Sin (90-30)
=> cos 40 . Sin 30 + SIN 40 . CoS 30
= SIN (40 +30)
Sin 70
similarly
solve 2nd one
vsr
sin (a+b) = sin a. CoS b + cos a. Sin b
CoS ( a-b) = cos a . CoS b + SIN a . Sin b
1) CoS 40 . CoS (90-60) + SIN 40 . Sin (90-30)
=> cos 40 . Sin 30 + SIN 40 . CoS 30
= SIN (40 +30)
Sin 70
similarly
solve 2nd one
vsr
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