Other Equations Ex. Solve 3x 4 = 48x2

Ex. Solve x3 – 3x2 + 3x – 9 = 0 2

Ex. Solve x 4 – 3x2 + 2 = 0 3

When solving equations with radicals or variables on the bottom, check all answers. Ex. Solve 4

Ex. Solve 5

6

Ex. Solve 7

Ex. Solve 8

9

Ex. Solve 10

11

Ex. A ski club charted a bus for a ski trip at a cost of $480 Ex. A ski club charted a bus for a ski trip at a cost of $480. In an attempt to lower the bus fare per skier, the club invited nonmembers to go along. After five nonmembers joined the trip, the fare per skier decreased by $4.80. How many club members are going on the trip? 12

Compound Interest 13

Ex. When you were born, your grandparents deposited $5000 in an account that compounds interest quarterly. On your 25th birthday, the value of the investment is $25,062.59. What is the annual interest rate on the account? 14

Practice Problems Section 1.6 Problems 1, 9, 13, 31, 59, 67, 91 15

Inequalities This means that we’ll use < > ≤ and ≥ Ex. Express each interval as an inequality. Is it bounded? (-3, 5] (-3, ∞) [0, 2] (-∞, ∞) 16 16

To solve inequalities, change them to equalities and then check the intervals. [If you want treat as an equality, remember that multiplying or dividing by a negative switches the inequality] Ex. Solve 5x – 7 > 3x + 9 17

Ex. Solve -3 < 6x – 1 < 3 18

|x| < 3 means x is anything between 3 and -3 -3 < x < 3 |x| > 3 means x is anything outside 3 and -3 x < -3 or x > 3 19

Ex. Solve |x – 5| < 2 20

Ex. Solve |x +3| ≥ 7 21

Ex. You are choosing between two cell phone plans. Plan A costs $49 Ex. You are choosing between two cell phone plans. Plan A costs $49.99 per month for 500 minutes plus $0.40 for each additional minute. Plan B costs $45.99 per month for 500 minutes plus $0.45 for each additional minute. How many additional minutes must you use in one month for Plan B to cost more than Plan A? 22

Practice Problems Section 1.7 Problems 1, 25, 37, 49, 91 23

More Inequalities Ex. Solve x2 – x – 6 < 0 24 24

Ex. Solve 2x3 – 3x2 – 32x > -48 25

Ex. Solve x2 + 2x + 4 > 0 Ex. Solve x2 + 2x + 4 < 0 26

Ex. Solve x2 + 2x + 1 ≤ 0 Ex. Solve x2 + 2x + 1 > 0 27

Ex. Solve 28

Ex. A projectile is fired straight upward from the ground with an initial velocity of 384 ft/sec. During what time period will its height exceed 2000 ft? [s = -16t2 + v0t + s0] 29

Ex. The revenue and cost equations for a product are R = x(50 – 0.0002x) and C = 12x + 150,000 where R and C are measured in dollars and x is the number of units sold. How many units must be sold to obtain a profit of at least $1,650,000? What is the price per unit? 30

Ex. Find the domain of 31

Practice Problems Section 1.8 Problems 13, 21, 25, 39, 55 32