Помогите!!! tg^2*120-ctg^2*120-10/3sin^2*120+cos^2*120

Question

Помогите!!!
tg^2*120-ctg^2*120-10/3sin^2*120+cos^2*120

Answer 1

=tg²(180-60) - ctg²(180-60) - 10/3sin²(180-60)+cos²(180-60)=tg²60-ctg60-10/3sin60+cos²60=(√3)²-(√3/3)²-10/3(√3/2)²+(1/2)²=3-3/9-10/3*3/4+1/4=

3-1/3-2,5+0,25=-1/3-3/4=-13/12=-1целая1/12