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 Difference identity:

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

\Rightarrow True

\frac{4 sin ^{2} ( t )}{tan ^{2} ( t )} = 4 cos^{2} (t)

\frac{csc ^{2} ( t )}{csc ^{2} ( t ) - 2} = sec (2 t)

cos^{2} (x) - sin^{2} (x) = 1 - sin^{2} (x)

sin (x) \cdot tan (x) + cos (x) = sec (x)

tan (2 x) = tan (x + 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