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Home / Algebra / Graphing and Functions / The Definition of a Function
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Section 3.4 : The Definition of a Function

For problems 1 – 6 determine if the given relation is a function.

  1. {(0,1),(2,6),(9,4),(7,2),(12,3)}
  2. {(4,1),(2,1),(0,1),(3,1)}
  3. {(0,4),(0,6),(0,8)}
  4. {(1,6),(3,4),(7,6),(2,10)}
  5. {(0,1),(2,3),(4,5),(6,7),(8,9),(10,11),(12,13)}
  6. {(7,0),(4,2),(4,1),(2,3),(6,0)}

For problems 7 – 13 determine if the given equation is a function.

  1. y=25x+75
  2. y=3x2+4x+1
  3. y=2x4
  4. y2=103x
  5. y2=x2+1
  6. y4+x3=1
  7. y3+x4=1
  8. Given A(t)=7t+2 determine each of the following.
    1. A(9)
    2. A(0)
    3. A(2)
    4. A(6x)
    5. A(t2+1)
  9. Given f(x)=3x determine each of the following.
    1. f(4)
    2. f(13)
    3. f(67)
    4. f(4t+2)
    5. f(6x)
  10. Given h(w)=2w+10 determine each of the following.
    1. h(1)
    2. h(0)
    3. h(3)
    4. h(2t)
    5. h(w+4)
  11. Given P(x)=32xx2 determine each of the following.
    1. P(6)
    2. P(0)
    3. P(3)
    4. P(z2)
    5. P(4x)
  12. Given f(z)=2z3z2 determine each of the following.
    1. f(1)
    2. f(0)
    3. f(4)
    4. f(12t)
    5. f(z1)
  13. Given g(t)={2+tif t10t7if t<10 determine each of the following.
    1. g(14)
    2. g(10)
    3. g(1)
  14. Given f(x)={4x2if x<46xif x4 determine each of the following.
    1. f(6)
    2. f(4)
    3. f(3)
  15. Given g(x)={12xif x7x2+1if 7<x<113xif x11 determine each of the following.
    1. g(2)
    2. g(7)
    3. g(8)
    4. g(11)
    5. g(14)
  16. Given A(w)={12if w>82+3wif 10w81if w<10 determine each of the following.
    1. A(12)
    2. A(10)
    3. A(9)
    4. A(8)
    5. A(0)
  17. Given f(x)={2xif x<64+xif x=6x2if x>6 determine each of the following.
    1. f(0)
    2. f(2)
    3. f(6)
    4. f(8)
    5. f(10)

For problems 24 – 28 compute the difference quotient for the given function. The difference quotient for the function f(x) is defined to be,

f(x+h)f(x)h
  1. f(x)=8x1
  2. f(x)=3x2
  3. f(x)=7x2
  4. f(x)=3x2+7x4
  5. f(x)=2x

For problems 29 – 39 determine the domain of the function.

  1. f(x)=9x
  2. P(z)=z24
  3. h(x)=2+x8x1
  4. A(t)=t24t2+6t7
  5. h(w)=w2+3w+2w2+12w+36
  6. g(x)=10x15
  7. f(t)=10t64t
  8. f(w)=w+72w
  9. A(z)=z29z
  10. h(z)=z2z20
  11. g(t)=6+t5t10