2 Answers | Add Yours
It is given that `sin X = 4/5` .
Use the identity `sin^2X + cos^2X = 1`
=> `(4/5)^2 + cos^2 X = 1`
=> `cos^2 X = 1 - 16/25`
=> `cos^2 X = 9/25`
=> `cos X = 3/5 or cos X = -3/5`
This can give two values of tan X, `(sin X)/(cos X)` can be `(4/5)/(3/5) = 4/3`
tan X could be `(4/5)/(-3/5) = -4/3` but it is seen that `sin(tan^-1(-4/3)) = -4/5`
The value of `tan X = 4/3`
If sin X = 4/5, what is tan X?
sin of an angle is Perpendicual divided by Hypotenuse for the angle of a right-angled triangle at base.
Let "k" be multiplier so that
In this case, the Perpendicular = 4k and Hypotenuse = 5k
The base of triangle = sqrt((Hypotenuse)^2-(Perpedicular)^2)
The base of triangle = sqrt((5k)^2-(4k)^2) = sqrt(25-16)*k = 3k
tanX = perpendicular/base = 4/3
The value of tan X = 4/3 when sin X = 4/5
We’ve answered 319,205 questions. We can answer yours, too.Ask a question