Найдите tgA если a)cosA=5/13 б)cosA=0,6 в)sinA=3/5 г)sinA=0,8

Question

Найдите tgA если a)cosA=5/13 б)cosA=0,6 в)sinA=3/5 г)sinA=0,8

Answer 1

tgA если:
 a)cosA=5/13, sinA = √(1-cos²A) = √(1-(25/169)) = √(144/169) = 12/13.
    tgA = sinA/cosA = (12/13)*(13/5) = 12/5 = 2,4.
 б)cosA=0,6, sinA = √(1-cos²A) = √(1-(36/100)) = √(64/100) = 8/10.
    tgA = sinA/cosA = (8/10)*(10/6) = 8/6 = 4/3 ≈ 1,333.
 в)sinA=3/5, cosA =  √(1-sin²A) = √(1-(9/25)) = √(16/25) = 4/5.
    tgA = sinA/cosA = (3/5)*(5/4) = 3/4 = 0,75.
 г)sinA=0,8, cosA =  √(1-sin²A) = √(1-(64/100)) = √(36/100) = 6/10.
    tgA = sinA/cosA = (8/10)*(10/6) = 8/6 = 4/3 ≈ 1,333.