Question

In ∆ABC, right-angled at C, in which AB = 13 cm, BC = 12 cm and ∠ABC = θ. Determine the value of $si{n}^2\theta$ + $co{s}^2\theta$.

Answer 1

In ∆ABC, right-angled at C, applying pythagoras theorem,
$A{B}^2$ = $A{C}^2$+$B{C}^2$
${13}^2$ = $A{C}^2$+${12}^2$
$A{C}^2$ = $\sqrt{25}$
AC = 25 cm