Question

Sin a × ctg( П-a) + cos(-a)​

Answer 1

Ответ:

0

Объяснение:

ctg(п-a)= - ctg a

-cos a = cos a

-sin a ×ctg a + cos a= -cos a +cos a = 0

(ctg a= cosa/ sina), синус сокращается

Answer 2

It seems like you've provided a mathematical expression:

Sin(a) × cot(π - a) + cos(-a)

Let's break this down step by step:

1. Sin(a) is the sine of angle 'a'.
2. cot(π - a) is the cotangent of the angle π - a. The cotangent is the reciprocal of the tangent, so cot(π - a) = 1/tan(π - a).
3. cos(-a) is the cosine of the negative angle -a.

You can use the following trigonometric identities to simplify this expression further:

1. sin(π - x) = sin(x)
2. tan(π - x) = -tan(x)
3. cos(-x) = cos(x)

Now, let's apply these identities to your expression:

Sin(a) × cot(π - a) + cos(-a) = Sin(a) × (-tan(a)) + cos(a) (Using the trigonometric identities above) = -Sin(a) × tan(a) + cos(a)

Depending on the values of 'a' (in radians), you can calculate the specific numerical value of this expression. If you have a particular value of 'a' in mind, please provide it, and I can help you calculate the result.