Questions asked
5) \( 4 \cos ^{2} x+4 \cos x-3=0 \) 6) \( 4 \cos ^{2} x-\cos x-3=0 \) 7) \( 4 \sin ^{2} x+4 \sin x-3=0 \) 8) \( \operatorname{ctg}^{2} x+\operatorname{ctg} x-2=0 \) 9) \( \sin ^{2} x-3 \sin x+2=0 \)
