Question

Cost A=0.6489

take the inverse cosine of both sides

Answer 1

I am not quite sure what the question asks for,
But this is what i assume it wants:

Cos A= 0.6489
In this given one, we basically find the size of the angle A
we do cosine inverse on both sides to get the size of the angle A

`cos^(-1)` : It looks like this in the calculator

`cos^(-1)` × cos A=
`cos^(-1)`(0.6489)
(
`cos^(-1)` and cos cancels out)
A=
`cos^(-1)`(0.6489)
A=49.54°
check:
cos 49.54=0.6489 (its right!)