Solving Equations

Exercise 1

1.

Find the domain of each function

(a) 8x + 3 = 4 + 8x

(b) 7(x – 2) - 2x = 5x - 14

(c) 12 + 4x = –2(2x – 6) (e) 12 + 4x = –2(2x – 6)

Exercise 3

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3−2? (?)?(?) = 2?2−3?

(?)?(?) = √|?| (?)?(?) = √?2 − 9 (?)?(?) = √5 − ?2

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(?)?(?) = √? − 4? − 5……………………..

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Let f be a function defined by?(?) = (? − 2) function f.

,? ≥ 2. Find the inverse of the …………………………………………………………………………………………

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The function ?(?) = |?| is invertible on R (i.e. admits an inverse)? Explain. …………………………………………………………………………………………

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Exercise 2

Determine if the equation has one solution, no solution or infinitely many solutions.

Solve each equation or inequality for x. Plot your solution on a number line

  1. (?−3)2=49
  2. 4(2?−3)+5=9
  3. 3?–5>16 4. −(?+5)≤3
  4. ?(?2−2)≥0

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Exercise 4

Solve each equation or inequality

  1. 2?2−?=−3

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  1. 2?2−?<−3 …………………………………………………………………………………………

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  1. = − ?2 2?2

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  1. ?+2=2√2?−7 …………………………………………………………………………………………

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Exercise 5

Solve the systems

  1. {4?−3?−2=3?−7?}

? + 5? − 2 = ? + 4

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2? + ? + 6? = 3

  1. { ?−?+4?=1 }

3? + 2? − 2? = 2

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Exercise 6

A person invested $ 120,000, part at an interest rate at 4% annually and the remainder at 5% annually. The total interest at the end of one year was equivalent to an annual 4.5% rate on the entire $ 120,000. How much was invested at each rate.

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Exercise 7

The Davis company manufactures a product that has a unit selling prices of $20 and a unit cost of $15. If fixed costs are $600,000, determine the least number of units that must be sold for the company to have a profit.

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