Question

Determine o valor de x
a)sem(x-10°)=cos30°

Answer 1

$\mathsf{cos(30^{\circ})=sen(90^{\circ}-30^{\circ})} \\ \mathsf{ =sen(60^{\circ})}$

$\mathsf{sen(x-10^{\circ})=cos(30^{\circ})}$

$\mathsf{sen(x-10^{\circ})=sen(60^{\circ})}\\\mathsf{x-10^{\circ}=60^{\circ}}\\\mathsf{x=60^{\circ}+10^{\circ}}\\\boxed{\boxed{\mathsf{x=70^{\circ}}}}$