In a special right triangle, A=5 B=? C=8 what is B, sin, cos, tan, can, sec and cot?

5² + B² = 8²

25 + B² = 64

Subtract 25 from both sides. 64 - 25 = 39

B² = 39

B = √39

As far as the rest, you would have to provide which angle you are referencing and a diagram so we can see where the legs and hypotenuse of the triangle lay.