Question

Ctg^2 210+ctg^2 120+tg^2 135 Вычислить

Answer 1

Ctg² 210° + ctg² 120° + tg² 135° = ctg²(180 + 30) + ctg²(90 + 30) + tg²(90 + 45)=
= ctg²30 + tg²30 + ctg²45 = (√3)² + (1/√3)² + 1 = 3 + 1/3 + 1 = (4)1/3

Answer 2

Ctg²210+ctg²120+tg²135=ctg²(180+30)+ctg²(90+30)+tg²(180-45)=
=ctg²30+tg²30+tg²45=3+1/3+1=4 1/3