Question

在直角三角形中角C等于九十度.AC等于十三分之五AB.则tanB等于

Answer 1

AC等于十三分之五AB

AC/AB = 5/13

tanB=AC/BC = AC/√(AB^2-AC^2) = (AC/AB)/√{1-(AC/AB)^2} = (5/13)/√{1-(5/13)^2} = 5/12