jika a+b = π/3 dan cos A cos B = 5/8 , nilai (A-B) = tolong pake cara

Trigonometri

(A+B) = π/3
cos (π/3)= 1/2
cos (A + B) = cos A cos B - sin A sin B
cos A cos B -  sin A sin B = 1/2

cos A cos B = 5/8
5/8 - sin A sin B  = 1/2
sin A sin B = 5/8 - 1/2 = 1/8

cos (A - B) = cos A cos B + sin A sin B
cos(A - B ) = 5/8 + 1/8 = 6/8 = 3/4
(A- B) = cos⁻¹ (3/4)  ---> dgn alat hitung  (A- B) = 41,41°