Question

Value of sin(45°+0) cos(15 +0)
cos(45+)
sinf 15°+0) is :-
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Answer 1

Answer:

1/8

Step-by-step explanation:

= sin45° . cos15° . cos45° . sin15°

=1/√2 . cos(45°-30°) . 1/√2 . sin(45°-30°)

= 1/2 . [cos45°.cos30°+sin45°.sin30°] . [sin45°.cos30° - cos45°.sin30°]

= 1/2 [1/√2 .√3/2 . + 1/√2 . 1/2 ] . [1/√2 . √3/2 - 1/√2 . 1/2 ]

= 1/2 × 1/√2 [√3/2 + 1/2 ] × 1/√2 [√3/2-1/2]

= 1/2 . 1/2 [√3/2+1/2]. [√3/2-1/2]

= 1/4[(√3/2)^2 - (1/2)^2 ]

= 1/4[3/4 - 1/4 ]

= 1/4 × 2/4

= 1/4 × 1/2

= 1/8 Ans

Good Luck.