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:
What I think are the answers are C,D, and A, hope this helps.
Step-by-step explanation:
Answer:
Number of drink = 5
Number of pretzel = 9
Step-by-step explanation:
Given:
Cost of each drink = $4
Cost of each pretzel = $5
Total money = 65
Total number of drink and pretzel = 14
Find:
Number of drink and pretzel
Computation:
Number of drink = x
Number of pretzel = 14 - x
So,
x(4) + (14-x)5 = 65
4x + 70 - 5x = 65
x = 5
Number of drink = 5
Number of pretzel = 14 - x
Number of pretzel = 14 - 5 = 9
Answer:
5.5 gallons
Step-by-step explanation:
set up a proportion; Liters in numerator and Gallons in denominator
let x = approx number of gallons
<u> 21 </u> = <u> 3.8 </u>
x 1
3.8x = 21
x = 21 ÷ 3.8
x ≈ 5.5
