Hello,
y=2xe^x
y'=2(e^x+xe^x)=2(x+1)e^x
y''=2(e^x+(x+1)e^x)=2(x+2)e^x
x |-infinite -2 0 +infinite
e^x | ++++++++++++++++++
x+2 |------------0 +++++++++++
y'' | -----------0 +++++++++++
y''<0 if x<-2
<span>The interval on which the graph is concave down is (-infinite -2[</span>
Answer:
The answer is:
30 minutes.
Step-by-step explanation:
We are given the following information:
at 160 m/min, tool life = 5 min.
at 120 m/min, tool life = 17 min.
This means that as the speed reduced from 160 m/min to 120 m/min, the tool life increased from 5 min. to 17 min, hence the difference between the changes are:
speed = 160 - 120 = 40 m/min
tool life = 17 - 5 = 12 min.
Therefore, it can be concluded that a change of speed of 40 m/min, increases the tool life by 12 min.
40 m/min = 12 min
∴ 1 m/min = 12/40 min.
∴ 100 m/min = 12/40 × 100 = 0.3 × 100 =30 min.
Answer:
30x - 18
Step-by-step explanation:
6(5x - 3)
To distribute, multiply the outside number by everything inside the parentheses.
6 x 5x = 30x
6 x -3 = -18
30x - 18
I hope this helps!