24: The function f(x)= 3x (x-4) has a
Answers
Answered by
0
Answer:
′
(x)=
(x−4)
2
(x−4)(3−2x)−(t+3x−x
2
)⋅1
=
(x−4)
2
(x−12−2x
2
)−(t+3x−x
2
)
=
(x−4)
2
−(12+t)−2x−x
2
=
(x−4)
2
−(x
2
+2x+(12+t))
f
′
(x)=0 has two roots
⇒−(x
2
+2x+12+t)=0 has two roots
⇒ Discriminant >0
D=2
2
−4(12+t)>0
⇒4(1−(12+t))>0
⇒−(t+11)>0
⇒t+11<0
⇒t<−11
Similar questions