Tolong bantu kak saya doakan rejekinya tambah lancar

Tolong bantu kak saya doakan rejekinya tambah lancar

$cos(x) - sin(x) = m - 1 \ {(cos(x) - sin(x))}^{2} = {(m - 1)}^{2} \ {cos}^{2} (x) - 2 cos(x) sin(x) + {sin}^{2} (x) = {m}^{2} - 2m + 1 \ {cos}^{2} (x)+ {sin}^{2} (x)- 2 cos(x) sin(x) = {m}^{2} - 2m + 1 \ 1 - 2 cos(x) sin(x) = {m}^{2} - 2m + 1 \ - 2 sin(x) cos(x) = {m}^{2} - 2m \ - sin(2x) = {m}^{2} - 2m \ sin(2x) = 2m - {m}^{2}$