Math, asked by Anfal1, 2 months ago

find the value of Sin (75°).
Hence, find cos (15°)

Answers

Answered by sharmaridhima008
3

Answer:

Sin 75 = Sin(45+30)…………………..(1)

By applying the formula

Sin (A + B) = Sin A. Cos B + Cos A. Sin B

Sin (45 + 30) = Sin 45. Cos 30 + Cos 45. Sin 30…………………..(2)

Sin Values

sin 0° = √(0/4) = 0

sin 30° = √(1/4) = ½

sin 45° = √(2/4) = 1/√2

sin 60° = √3/4 = √3/2

cos 90° = √(4/4) = 1

Cos Values

cos 0° = √(4/4) = 1

cos 30° = √(3/4) = √3/2

cos 45° = √(2/4) = 1/√2

cos 60° = √(1/4) = 1/2

cos 90° = √(0/4) = 0

Substitute the value of sin 30, sin 45, cos 30 and cos 45 degrees, then equation (2) will becomes

Sin (45 + 30) = Sin 45. Cos 30 + Cos 45. Sin 30

Sin (45 + 30) = 1/√2 . √3/2 + 1/√2 . 1/2

Sin (45 + 30) = (√3 + 1) / 2√2

Hence the value of Sin 75 degree is equal to

(√3 + 1) / 2√2.

Cos15 = Cos(45–30)…………………..(1)

By applying the formula

Cos (A – B) = Cos A. Cos B + Sin A. Sin B

Cos (45 – 30) = Cos 45. Cos 30 + Sin 45. Sin 30…………………..(2)

Sin Values

sin 0° = √(0/4) = 0

sin 30° = √(1/4) = ½

sin 45° = √(2/4) = 1/√2

sin 60° = √3/4 = √3/2

cos 90° = √(4/4) = 1

Cos Values

cos 0° = √(4/4) = 1

cos 30° = √(3/4) = √3/2

cos 45° = √(2/4) = 1/√2

cos 60° = √(1/4) = 1/2

cos 90° = √(0/4) = 0

Substitute the value of sin 30, sin 45, cos 30 and cos 45 degrees, then equation (2) will becomes

Cos (45 – 30) = 1/√2 . √3/2 + 1/√2 . 1/2

Cos 15 = √3/2√2 + 1/2√2

Cos 15 = √3+1/2√2

Answered by vinayashewale81
2

Step-by-step explanation:

I am confused in equation 4 th

please classify the assets, libilites, and capital

my answer getting wrong so please tell me

Similar questions