Question

Sina+cosa=asina*cosa=?

Answer 1

Объяснение:

$sin\alpha +cos\alpha =a\ \ \ \ \ sin\alpha *cos\alpha =?\\(sin\alpha +cos\alpha )^2=a^2\\sin^2\alpha +2*sin\alpha *cos\alpha +cos^2\alpha =a^2\\1+2*sin\alpha*cos\alpha =a^2\\2*sin\alpha *cos\alpha =a^2-1\ |:2\\sin\alpha *cos\alpha =\frac{a^2-1}{2} .$

Answer 2

To find the value of asin(a) * cos(a) where a is an angle in radians, you can use trigonometric identities. First, you can rewrite the expression asin(a) * cos(a) as follows:

asin(a) * cos(a) = (sin(a)) * (cos(a))

Now, you can use the trigonometric identity:

sin(2a) = 2 * sin(a) * cos(a)

To find sin(a) * cos(a), you can rearrange the identity as follows:

sin(a) * cos(a) = (1/2) * sin(2a)

So, sin(a) * cos(a) is equal to half of the sine of twice the angle a.