Question

Найдите 24cos2a,если sin a=-0,2

Answer 1

24 Cos 2a = 24 [ 1 - 2 Sin ^2 a] = 24 [ 1 - 2 *(- 0,2)^2] = 24 * (1 - 0,08)=
= 24*0,92= 22,08

Answer 2

To find the value of 24cos^2(a) given that sin(a) = -0.2, we can use the Pythagorean trigonometric identity:

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

Given sin(a) = -0.2, we can square it to get sin^2(a):

sin^2(a) = (-0.2)^2 = 0.04

Now, let's use the Pythagorean identity to find cos^2(a):

cos^2(a) = 1 - sin^2(a) cos^2(a) = 1 - 0.04 cos^2(a) = 0.96

Finally, to find 24cos^2(a), we multiply the value of cos^2(a) by 24:

24cos^2(a) = 24 * 0.96 = 23.04

So, the value of 24cos^2(a) is 23.04.