Cos 43*cos 17*-sin43*sin17*

Предыдущий
вопрос Следующий
вопрос

The expression cos(43)cos(17)-sin(43)*sin(17) simplifies to 0.

This can be shown using the double angle formula for cosine, which states cos(2θ) = cos^2(θ) - sin^2(θ).

In this case, let's set θ = 43 and apply the formula:
cos(86) = cos^2(43) - sin^2(43)

Similarly, let's set θ = 17 and apply the formula:
cos(34) = cos^2(17) - sin^2(17)

So cos(43)cos(17)-sin(43)sin(17) is equal to cos(86)-sin(34), which further simplifies to 0.