Question

Cos*cosb-cos(a+b)/cos(a-b)-sina*sinb

Answer 1

Применены формулы сложения

Answer 2

The expression you provided seems to be a combination of trigonometric functions. Let's break it down step by step:

Coscosb - cos(a+b) / cos(a-b) - sinasinb

Step 1: Simplify cos(a+b) using the cosine addition formula: cos(a+b) = cos(a)*cos(b) - sin(a)*sin(b)

Now the expression becomes:

cos*cosb - (cos(a)*cos(b) - sin(a)sin(b)) / cos(a-b) - sinasinb

Step 2: Simplify cos(a-b) using the cosine subtraction formula: cos(a-b) = cos(a)*cos(b) + sin(a)*sin(b)

The expression becomes:

cos*cosb - (cos(a)*cos(b) - sin(a)*sin(b)) / (cos(a)*cos(b) + sin(a)sin(b)) - sinasinb

Step 3: Combine the terms in the numerator: cos*cosb - cos(a)*cos(b) + sin(a)*sin(b) / (cos(a)*cos(b) + sin(a)sin(b)) - sinasinb

Step 4: Multiply the entire expression by the conjugate of the denominator to simplify:

[cos*cosb - cos(a)*cos(b) + sin(a)*sin(b)] * [cos(a)*cos(b) - sin(a)*sin(b)] / [(cos(a)*cos(b) + sin(a)*sin(b)) * (cos(a)*cos(b) - sin(a)sin(b))] - sinasinb

Step 5: Simplify further:

[cos*cosb - cos(a)*cos(b) + sin(a)*sin(b)] * [cos(a)*cos(b) - sin(a)sin(b)] / [cos(a)^2 * cos(b)^2 - sin(a)^2 * sin(b)^2] - sinasinb

Please note that there might be other possible simplifications or transformations depending on the context or any specific constraints provided.