Is cos(α+β)=cos(α)cos(β)-sin(α)sin(β) ?

The answer to whether cos(α+β)=cos(α)cos(β)-sin(α)sin(β) is True

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prove cos(α+β)=cos(α)cos(β)-sin(α)sin(β)

prove

cos (α + β) = cos (α) cos (β) - sin (α) sin (β)

True

Solution steps

cos (α + β) = cos (α) cos (β) - sin (α) sin (β)

Use the Angle Sum identity:

cos (s + t) = cos (s) cos (t) - sin (s) sin (t)

\Rightarrow True

p ro v e cos (x) + cos (x) tan^{2} (x) = sec (x)

p ro v e tan (x) csc (x) cos (x) = 1

p ro v e cos (3 x) + cos (x) = 2 cos (2 x) cos (x)

p ro v e sin (4 x) = 2 sin (2 x) cos (2 x)

p ro v e \frac{cos ( x ) cot ( x )}{1 - sin ( x )} - 1 = csc (x)

Is cos(α+β)=cos(α)cos(β)-sin(α)sin(β) ?
The answer to whether cos(α+β)=cos(α)cos(β)-sin(α)sin(β) is True