Question

Sin (-135) помогите по формуле приведения

Answer 1

- sin 135 = - sin(90+45) = -sin 45

Answer 2

Solving sin(-135) using the sum and difference formulas

To solve sin(-135) using the sum and difference formulas, we can express -135 as the sum or difference of two known angles and then use the trigonometric identities to simplify the expression.

Using the sum and difference formulas, we can express -135 as the difference of 45 and 180 degrees:

-135 = -180 + 45

Now, we can use the trigonometric identities to simplify sin(-135) using the following steps:

1. sin(90 + A) = cos(A) - Since 135 - 90 = 45, we can use this identity to simplify sin(-135): - sin(90 + 45) = cos(45) = (2) / 2 [[1]](https://uchi.ru/otvety/questions/vichislit-sin-135-gradusov-po-formule-privideniya)

2. sin(180 - A) = sin(A) - We can also use this identity to simplify sin(-135): - sin(180 - 45) = sin(45) = (2) / 2 [[1]](https://uchi.ru/otvety/questions/vichislit-sin-135-gradusov-po-formule-privideniya)

Therefore, sin(-135) = (2) / 2.

This simplification is based on the trigonometric sum and difference formulas and the corresponding trigonometric identities.

I hope this helps! If you have any further questions, feel free to ask.