Sin of A= opposite / hypotenuse = 4 (sides of the right triangle are congruent, it's an isoscles) / [tex]4* \sqrt{2} [/tex] = 1/ [tex] \sqrt{2} [/tex] = [tex] \sqrt{2} / 2[/tex]
Cos of A= adjacent / hypotenuse = 4 / [tex]4* \sqrt{2} [/tex] = 1/ square root of 2 = [tex] \sqrt{2} / 2[/tex]