Section 4.4
1. Find the definite integral.

3
0
Use your calculator
x 2 dx
2. Find the definite integral.

2
1
1
dx
x
3. Find the definite integral.
  6x  4x  1 dx
2
2
1
3. Find the definite integral.
4. Find the definite integral.
  8  4 x  dx
8
0
3
 x
2
5. Find the definite integral.
1
1
 x2  dx
6. Find the definite integral.

2
0
ex 2 dx
 1
0  x2 
2
7. Find the definite integral.

 dx
1
8. GENERAL: Electrical Consumption – On a hot summer afternoon, York College’s
electricity consumption is – 3t 2 + 18t + 10 units per hour, where t is the number
of hours after noon (0 ≤ t ≤ 6). Find the total consumption of electricity between
the hours of 1 and 5 p.m.
   3x  18x  10 dx
5
2
1
The total consumption of electricity will be 132 units.
9. BUSINESS: Cost - A company’s marginal cost function is MC (x) = 6e - .02x ,
where x is the number of units. Find the total cost of the first hundred units.
The total cost of the first hundred units will be $259.40.
10. BUSINESS: Tin Consumption – World consumption of tine is running at the
rate of 0.26 e .01t million metric tons per year, where t is measured in years
and t = 0 corresponds to the beginning of 2008. find the total consumption of
tine from the beginning of 2008 to the beginning of 2018.
The total consumption of tin from 2008 to 2018 will be 2.73 million
metric tons..
11. BEHAVIORAL SCIENCE: Learning – A student can memorize words at the
rate of 6 e -t/5 words per minute after t minutes. Find the total number of
words the student can memorize in the first 10 minutes.
The student can memorize about 26 words in the first 10
minutes.
12. BIOMEDICAL: Drug Absorption – An oral medicine is absorbed in the blood
stream at the rate of 6 e - 0.04t milligrams per minute. Where t is the number
of minutes since the drug has been administered. Find the total amount of
medication absorbed within the first 30 minutes.
About 105 milligrams of drug will be absorbed in the first 30
minutes.
13. BUSINESS: Sales – A car dealer predicts that new cars will sell at the rate
of 8xe - 0.1x sales per week x. Find the total sales in the first half year.
About 586 cars will be sold in the first half year.