Glede na cottheta = -12 / 5 in 270

Glede na cottheta = -12 / 5 in 270
Anonim

Odgovor:

#rarrcsc (theta / 2) = sqrt26 #

Pojasnilo:

Tukaj, #270^(@)##<## theta ##<##360^@#

# rarr135 ^ (@) ##<## theta / 2 ##<##180^@# To pomeni # theta / 2 # je v drugem kvadrantu, kjer #sin in csc # so pozitivni.

# rarrcottheta = -12 / 5 #

# rarrtantheta = -5 / 12 #

# rarrcostheta = 1 / sectheta = 1 / sqrt (1 + tan ^ 2theta) = 1 / sqrt (1 + (- 5/12) ^ 2) = 12/13 #

#rarrcsc (theta / 2) = 1 / sin (theta / 2) = 1 / sqrt ((1-costheta) / 2) = 1 / sqrt ((1-12 / 13) / 2) = 1 / sqrt (1 / (26)) = sqrt26 #