Question

sa se calculeze cos^2 de 120(grade)+ sin^2 de 60(grade)

Answer 1

120 grade = (2/3)*pi
60 grade = pi/3
cos ^2((2/3)*pi)=(cos((2/3)*pi)^2=(-1/2)^2=1/4
sin^2 (pi/3)=(sin(pi/3))^2=(sqrt*(3)/2)^2=3/4
1/4+3/4=4/4=1

Raspuns cos^2 de 120(grade)+ sin^2 de 60(grade)=1

*sqrt- radical de ordinul 2