Question

Найдите значения sina,cosa,tga и ctg, если 1) a=3П/2, 2) а=3П/4, 3) а=5П/6.

Answer 1

1) sin(3π/2) = - 1

cos(3π/2) = 0

tg(3π/2) = не определён

ctg(3π/2) = 0

2) sin(3π/4) = sin(π - π/4) = sin(π/4) = √2/2

cos(3π/4) = cos(π - π/4) = - cos(π/4) = - √2/2

tg(3π/4) = tg(π - π/4) = - tg(π/4) = - 1

ctg(3π/4) = ctg(π - π/4) = - ctg(π/4) = - 1

3) sin(5π/6) = sin(π - π/6) = sin(π/6) = 1/2 = 0,5

cos(5π/6) = cos(π - π/6) = - cos(π/6) = - √3/2

tg(5π/6) = tg(π - π/6) = - tg(π/6) = - √3/3

ctg(5π/6) = ctg(π - π/6) = - ctg(π/6) = - √3