Pg. 255/268 Homework

• Pg. 277 #32 – 40 allPg. 292 #1 – 8, 13 – 19 odd

• #6 left 2, up 4 #14 Graph• #24 x = #28 x = 6• #35 Graph #51 r = 6.35, h = 9, V = 380• #1 Graph #3 a) dec b) inc c) dec• #5 down 4 #7 right 3• #9 left 1, up 7 #15 a = c

7 56 14

8 8 4

5.1 Exponential Functions

• Suppose the half-life of a certain radioactive substance is 20 days and there are 5g present initially. Draw a complete graph of an algebraic representation of this problem situation and find when there will be less than 1g of the substance remaining.

5.2 Simple and Compound Interest

Simple Interest• Suppose P dollars are

invested at a simple interest rate r, then the simple interest formula for the total amount T after n interest periods is:

T = P(1 + nr)

Example:• Silvia deposits $500 in an

account that pays 7% simple annual interest. How much will she have saved after 10 years?

5.2 Simple and Compound Interest

Compound Interest• Compound Interest is when

financial institutions pay interest on the interest.

• Suppose P dollars are invested at an interest rate r, then the compound interest formula for the total amount S after n interest periods is: S = P(1 + r/n)nt

Example• Suppose $500 is invested at

7% interest compounded annually. Find the value of the investment after 10 years.

• How much should be invested at 6.25% compounded semi-annually in order to have an investment of $1,500 after 5 years?

5.2 Simple and Compound Interest

Compound Interest• Suppose $1000 is invested

at 8%. Find the value of the investment after one year when it is compounded– Annually– Quarterly– Monthly– Weekly– Daily– Hourly

Continuous Interest• If P dollars are invested at

APR r (in decimal form) and compounded continuously, then the value of the investment after t years is given by:

S = Pert