Given sin α + cos α = 1 / 5, π ≤ α ≤ 2 π, the value of Tan α is obtained

Given sin α + cos α = 1 / 5, π ≤ α ≤ 2 π, the value of Tan α is obtained

sinα+cosα=1/5
and
sin²α+cos²α=1
LIANLI Kede
sinα=4/5 cosα=-3/5
thus
tanα=-4/3