Question

Найдите tgA, если CosA = -0,6

Answer 1

sinA=√(1-(0,6)²)=√0,64=0,8;

tgA=sinA/cosA=0,8/(-0,6)= -1 1/3.

Answer 2

To find the value of tangent (tg) of angle A, given the value of cosine (cos) of angle A, we can use the trigonometric identity:

tg^2(A) + 1 = cos^2(A)

First, we'll find the sine (sin) of angle A using the Pythagorean identity:

sin^2(A) + cos^2(A) = 1

sin^2(A) = 1 - cos^2(A) sin^2(A) = 1 - (-0.6)^2 sin^2(A) = 1 - 0.36 sin^2(A) = 0.64

Now, take the square root of both sides to get the value of sin(A):

sin(A) = √0.64 sin(A) = ±0.8

Since both sine and cosine are negative in the second quadrant (90° < A < 180°), the value of sin(A) is negative:

sin(A) = -0.8

Now, we can find the tangent (tg) of angle A using the definition of tangent:

tg(A) = sin(A) / cos(A) tg(A) = -0.8 / (-0.6) tg(A) = 0.8 / 0.6 tg(A) = 4/3

So, tg(A) = 4/3.