Answer
$c^{2}$ = $(7.9)^{2}$ + $(5.2)^{2}$ + 2*5.2*7.9 cos 83°
Work Step by Step
Given data
a=5.2,b=7.9, γ=83°
Using theorem 11.4.3
$c^{2}$ = $b^{2}$ + $a^{2}$ + 2ab cos γ
$c^{2}$ = $(7.9)^{2}$ + $(5.2)^{2}$ + 2*5.2*7.9 cos 83°
$c^{2}$ = $(7.9)^{2}$ + $(5.2)^{2}$ + 2*5.2*7.9 cos 83°
