Sincethe accent in the OP is put on a purely geometric solution, i can not even consider the chance to write $\cos^2 =1-\sin^2$, and rephrase the wanted equality, thus having a trigonometric function which is better suited to geometrical interpretations.. So this answer has two steps, first we reformulate the given identity in a mot-a-mot geometric manner, the geometric framework is
Iknow that cos is even while sin is odd, and I know $\cos(\pi)=\sin((\pi/2)-x)$, but I still can't figure the derivation of $\sin (a+b)$ from $\cos(a+b)=\cos(a)\cos
Usingthe fact that sin (A + B) = sin A cos B + cos A sin B and the differentiation, obtain the sum formula for cosines. Hard. Open in App. Solution. Verified by Toppr. sin (A + B) = sin A cos B + cos A sin B c o s (A + B)
i9CwHE3.