Respuesta :

Answer:

steps

Step-by-step explanation:

(1 + sinx)(1 - sinx) = 1 - sin²x = cos²x   or = cos² -x

cos -x = cos x

∴ (1 + sinx)(1 - sinx) will not equal cos -x, unless x = ±360° or 0°

where cos ±360° or cos 0° = 1