Question

(cos²x-1)(tan²x+1)=1-sec²x​

Answer 1

Respuesta:

Explicación paso a paso:

$(cos^2 x - 1)(tg^2 x + 1) = 1 - sec^2 x \\\ cos^2 x - 1 = - sen^2 x \\\ tg^2 x + 1 = \frac{1}{cos^2 x} = sec^2 x \\\ - sen^2 x.sec^2 x = 1 - sec^2 x \\\ - sen^2 x.sec^2 x + sec^2 x = 1 \\\ sec^2 x(- sen^2 x + 1) = 1 \\\ sec^2 x.cos^2 x = 1 \\\ sec^2 x = \frac{1}{cos^2 x}$

Espero haber ayudado.