Wie bewerten Sie #cos ((2pi) / 3) #?

Antworten:

# -1/2#

Erläuterung:

The angle # (2pi)/3" is in the 2nd quadrant "#
where the cos ratio has a negative value.

The related 'acute angle' to #(2pi)/3 =( pi -(2pi)/3) = pi/3 #

#rArr cos((2pi)/3) = - cos(pi/3) #

and using the #color(blue)" Exact value triangle"#

Bildquelle hier eingeben

# cos((2pi)/3) = - cos(pi/3) = -1/2 #