Question

Calculati: tg²30+ctg²45= ??

Answer 1

tg30°=1/√3  ;tg²30°=(1/√3)²=1/3
ctg45°=1  ;ctg²45°=1²=1

tg²30°+ctg²45°=1/3+1=4/3

Answer 2

tg 30=$\frac{ \sqrt{3} }{3}$ => tg^2 30 = ($\frac{ \sqrt{3} }{3}$)^2=$\frac{3}{9}$=$\frac{1}{3}$

ctg 45=1=>ctg^2 45=1^2=1

$tg^{2} 30+ ctg^{30} = \frac{1}{3}+1= \frac{4}{3}$