Question

value of sin 75 degrees
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Answer 1

Solution :-

As we know that , 75° can be written as 45° + 30°

So ,

• sin75° = sin(45° + 30°)

Now using sin(A + B) = sinAcosB + cosAsinB

By substituting the values of the angles , we have ,

=> sin75° = sin(45° + 30°) = sin45°cos30° + cos45°sin30°

=> sin75° = 1/√2 × 1/2 + 1/√2 × √3/2

=> sin75° = 1/2√2 + √3/2√2

=> sin75° = 1 + √3/2√2

Hence , sin75° = 1 + √3/2√2

Answer 2

Answer:

As we know that , 75° can be written as 45° + 30°

So ,

sin75° = sin(45° + 30°)

Now using sin(A + B) = sinAcosB + cosAsinB

By substituting the values of the angles , we have ,

=> sin75° = sin(45° + 30°) = sin45°cos30° + cos45°sin30°

=> sin75° = 1/√2 × 1/2 + 1/√2 × √3/2

=> sin75° = 1/2√2 + √3/2√2

=> sin75° = 1 + √3/2√2

Hence , sin75° = 1 + √3/2√2