" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
2)
tgα=√5
ctgα=1/tg
ctgα=1/√5=√5/5
tgα=sinα/cosα
√5=sinα/cosα /·cosα
cosα√5=sinα
sin²α+cos²α=1
(cosα√5)²+cos²α=1
5cos²α+cos²α=1
6cos²α=1
cos²α=1/6
cosα=√(1/6)=√6/6
sinα=√5·cosα=√5·√6/6=√30/6
odp:ctgα=√5/5, sinα=√30/6 , cosα=√6/6
2)sinα=1/3
(1/3)²+cos²α=1
1/9+cos²α=1
cos²α=1-1/9
cos²α=8/9
cos²α=√(8/9)=2√2/3 lub cosα=- 2√2/3
czyli π/2 <α >π zatem α∈(π/2,π) czyli cosα<0
tgα=sinα/cosα=1/3:(-2√2/3)=1/3·(-3/2√2)= -1/2√2=-√2/4
ctgα=cosα/sinα=-2√2/3 :1/3=-2√2/3·3/1 =-2√2
odp: cosα=-2√2/3 , tgα=-√2/4 , ctgα=-2√2