CUET Preparation Today
If $(2 \cos A+1)(2 \cos A-1)=0,0^{\circ}<A \leq 90^{\circ}$, then find the value of A. |
90° 45° 30° 60° |
60° |
( 2cosA - 1 ) ( 2cosA + 1 ) = 0 4cos2A - 1 = 0 cos2A = \(\frac{1}{4}\) cosA = \(\frac{1}{2}\) & we know , cos60º = \(\frac{1}{2}\) |
