Question

verify this identity tan (x+pi/2)= -cotx

Answer 1

tan(x+pi/2) = sin(x+pi/2)/cos(x+pi/2) = cos(x)/-sin(x) = -cot(x)

Answer 2

understand?

Answer 3

sin(x+pi/2) = cos(x) and cos(x+pi/2) = -sin(x)

Answer 4

@$w3G_Godd how did you get cos(x)/-sin(x)?

Answer 5

tan(anything) = sin(anything)/cos(anything)
so
tan(2) = sin(2)/cos(2)
tan(2x) = sin(2x)/cos(2x)
tan(puppy dog) = sin(puppy dog)/cos(puppy dog)
so
tan(x+pi/2) = sin(x+pi/2)/cos(x+pi/2)

Answer 6

better?

Answer 7

ya i got that, but why does it then flip to cos(x)/-sin(x)?

Answer 8

sin(x+pi/2) = sin(x)cos(pi/2) + cos(x)sin(pi/2) = 0+cos(x)=cos(x)

cos(x+pi/2)= cos(x)cos(pi/2) - sin(x)sin(pi/2)= 0-sin(x)=-sin(x)

Answer 9

sorry i just now saw this