Prove
Tan(x)+cot(x)=sec(x)/sin(x)

Step-by-step explanation:

tanx + cotx = secx / sinx

take left hand side

=tanx + cotx

=sinx/cosx + cosx/sinx

=sinx*sinx+cosx*cosx/sinx*cosx

=sin^2x + cos^2x/sinx*cosx

=1/sinx*cosx

=1/cosx * 1/sinx

=secx/sinx

at second last step i changed multiplication sign into divide sign and write the reciprocal of 1/sinx which is sinx.

-2

7 - 9 = -2

reversed:

-2 + 9 = 7