Question

Cos x² - senx² = 4 senx+1​

Answer 1

Explicación paso a paso:

${cos}^{2} x - {sen}^{2} x = 4senx + 1 \\ {cos}^{2} x - {sen}^{2} x = 4senx + {sen}^{2} x + {cos}^{2} x \\ - {sen}^{2} x = 4senx + {sen}^{2} x \\ 2 {sen}^{2} x = - 4senx \\ 2senx = - 4 \\ senx = \frac{ - 4}{2} \\ senx = - 2$