Nilai dari cos40°−cos50°sin50°−sin40°\frac{\cos40\degree-\cos50\degree}{\sin50\degree-\sin40\degree}sin50°−sin40°cos40°−cos50° adalah ....
111
133\frac{1}{3}\sqrt{3}313
−1-1−1
3\sqrt{3}3
−12-\frac{1}{2}−21