Question

If sinA = 2/3 then find cosA = ? with method please...

Answer 1

draw a triangle
\[\large\rm sin \theta =\frac{ opposite }{ hypotenuse } ~~~ \cos \theta=\frac{ adjacent }{ hypotenuse } ~~\tan \theta =\frac{ opposite }{ adjacent }\]

Answer 2

apply Pythagorean theorem to find side of right triangle \[\huge\rm a^2+b^2=c^2\]