Step-by-step explanation:
Hello, there!!!
I hope you mean the question is like the above problem in picture.
so, let's simply work with it.
here, we may use cosine rule,
so, according to cosine rule,
[tex] {c}^{2} = {a}^{2} + {b}^{2} - 2ab.cosc[/tex]
so, just put value of formulae here,
we get;
5^2 = 3^2 + 4^2 - (2×3×4) . cos thita
or, 25 = 9 + 16 -24 cos thita.
or, 24 cos thita = 0
or, cos thita = 0/25
or, cos thita = 0
now, taking cos to right side we get,
[tex] {cos}^{ - 1 } (0)[/tex]
now, after typing cos ^-1 (0) we get angle as 90°.
(note: in step {cos thita = 0} you couold directly write like; cos thita = cos 90°. and cos would be cancelled in it as cos 90°=0. but it is only applied in particular angle like 0°,30°,60°,..... which are identified or if you don't know you must use the method above using calculator and remember to put inverse {cos^-1}).
so, In this way we find angle.
I hope it helps....
