Question

2cos(3пи +а)+sin(пи/2-а)все делить на cos(пи-а)

Answer 1

Ответ:

Объяснение:

=(-2cosa+cosa) /(-cosa)=cosa/cosa=1

Answer 2

To simplify the expression (2cos(3π + а) + sin(π/2 - а)) / cos(π - а), we'll use trigonometric identities and simplify step by step:

Step 1: Utilize the periodicity of trigonometric functions to rewrite the arguments inside trigonometric functions.

cos(3π + а) = cos(3π)cos(а) - sin(3π)sin(а) = -cos(а) sin(π/2 - а) = sin(π/2)cos(а) - cos(π/2)sin(а) = cos(а)

Step 2: Substitute these values back into the expression:

(2cos(3π + а) + sin(π/2 - а)) / cos(π - а) = (2*(-cos(а)) + cos(а)) / cos(π - а)

Step 3: Simplify further:

= (-2cos(а) + cos(а)) / cos(π - а) = (-cos(а)) / cos(π - а)

Step 4: Apply the trigonometric identity: cos(π - а) = -cos(а)

= (-cos(а)) / (-cos(а)) = 1

So, the simplified expression is equal to 1.