Question
If ( frac{cos 5 mathrm{A}}{cos mathrm{A}}+frac{sin 5 mathrm{A}}{sin mathrm{A}} equiv mathrm{a}+mathrm{b} cos 4 mathrm{A}, ) then find the value of ( frac{(mathrm{a}+mathrm{b})}{2} )

If ( frac{cos 5 mathrm{A}}{cos mathrm{A}}+frac{sin 5 mathrm{A}}{sin mathrm{A}} equiv mathrm{a}+mathrm{b} cos 4 mathrm{A}, ) then find the value of ( frac{(mathrm{a}+mathrm{b})}{2} )
Solution

The value of frac{a + b}{2} = 3
The step-by-step solution above.