find the value of 2 sin 15 cos 75
2 sin 150 cos 750 = ?
we know that :
2 sinA cosB = sin(A+B) + sin (A-B )
Here, A=150 , B =750
2 Sin 150 Cos 750 = sin (15 + 75) + sin (15 - 75 )
= sin 900 + sin (-60 )
( sin 90 = 1, sin (-60) = -root 3 /2 )
= 1 + (-root 3/ 2)
= 2 - root3
2
therefore, 2sin15 cos 75 = 2 - root 3
2
hope ...this will help u......:))))
we know that :
2 sinA cosB = sin(A+B) + sin (A-B )
Here, A=150 , B =750
2 Sin 150 Cos 750 = sin (15 + 75) + sin (15 - 75 )
= sin 900 + sin (-60 )
( sin 90 = 1, sin (-60) = -root 3 /2 )
= 1 + (-root 3/ 2)
= 2 - root3
2
therefore, 2sin15 cos 75 = 2 - root 3
2
hope ...this will help u......:))))