III (a)-sm² L-cos²2+1 = (5) cos²2.tg-2 + sin^2. ctg*2=

Упростим выражение:

1. $$-sin^2 \alpha - cos^2 \alpha + 1 = -(sin^2 \alpha + cos^2 \alpha) + 1 = -1 + 1 = 0$$
2. $$cos^2 \alpha \cdot tg^2 \alpha + sin^2 \alpha \cdot ctg^2 \alpha = cos^2 \alpha \cdot \frac{sin^2 \alpha}{cos^2 \alpha} + sin^2 \alpha \cdot \frac{cos^2 \alpha}{sin^2 \alpha} = sin^2 \alpha + cos^2 \alpha = 1$$

Ответ:

1. $$0$$
2. $$1$$