Question

num triângulo ABC A=3 B=1 C=60° calcular C

Answer 1

${c}^{2} = {3}^{2} + {1}^{2} - 2 \times 3 \times 1 \times \cos(60) \\ {c}^{2} = 9 + 1 - 6 \times \frac{1}{2} \\ {c}^{2} = 10 + 3 \\ c = \sqrt{7}$