MAT221: Introduction to Algebra
June 14, 2013
Compounded semiannually. P dollars is invested at annual interest rate r for 1 year. If the interest is compounded semiannually, then the polynomial P(1+r/2)2 represents the value of the investment after 1 year. Rewrite this expression without parentheses.
|P(1+r/2)2 |Squaring the expression- this is the same as multiplying the expression by itself 2 times.|
| | |
| |Simplify the expression using the FOIL method |
|P(1+r/2)(1+r/2) | |
| |Combined like terms r + r = 2r or r |
|P(r2/4+r/2+r/2+1) |2 2 2 |
| |Distribute P across the trinomial |
|P(r2/4+r+1) | |
| |Place all variables in descending order |
|Pr2/4+Pr+P | |
Now we are to try out our polynomial formula with the given sets of numerical information. |P = $200 and r = 10% |Interest rate as a decimal number r =.10 |
|Pr2/4+Pr+P |The expanded formula