((t^2-2t-15))/(t^2-9)/(t^2-3t)

Solution for ((t^2-2t-15))/(t^2-9)/(t^2-3t) equation:

D( t )

t^2-(3*t) = 0

t^2-9 = 0

t^2-(3*t) = 0

t^2-(3*t) = 0

t^2-3*t = 0

t^2-3*t = 0

DELTA = (-3)^2-(0*1*4)

DELTA = 9

DELTA > 0

t = (9^(1/2)+3)/(1*2) or t = (3-9^(1/2))/(1*2)

t = 3 or t = 0

t^2-9 = 0

t^2-9 = 0

1*t^2 = 9 // : 1

t^2 = 9

t^2 = 9 // ^ 1/2

abs(t) = 3

t = 3 or t = -3

t in (-oo:-3) U (-3:0) U (0:3) U (3:+oo)

((t^2-(2*t)-15)/(t^2-9))/(t^2-(3*t)) = 0

((t^2-2*t-15)/(t^2-9))/(t^2-3*t) = 0

(t^2-2*t-15)/((t^2-9)*(t^2-3*t)) = 0

t^2-2*t-15 = 0

t^2-2*t-15 = 0

DELTA = (-2)^2-(-15*1*4)

DELTA = 64

DELTA > 0

t = (64^(1/2)+2)/(1*2) or t = (2-64^(1/2))/(1*2)

t = 5 or t = -3

(t+3)*(t-5) = 0

t^2-3*t = 0

t*(t-3) = 0

t-3 = 0 // + 3

t = 3

t*(t-3) = 0

((t+3)*(t-5))/(t*(t^2-9)*(t-3)) = 0

( t+3 )

t+3 = 0 // - 3

t = -3

( t-5 )

t-5 = 0 // + 5

t = 5

t in { -3} 

t = 5