2Sin tita+2Cos tita=1.5.find tita

Answer 1

That's theta not tita

For ease of typing, I'll just use x.

2sinx + 2cosx = 1.5
sinx + cosx = 3/4

Now, since sin 45° = cos 45° = 1/√2,

sinx + cosx = √2 sin(x+45°)

Now we have

sin(x+45°) = 3/(4√2) = 0.53033
x+45° = 32°
x = -13°

You probably want values in [0,360°), so

x = 193° or 347°