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? asked in Science & MathematicsMathematics · 1 decade ago

can anyone solve these 3 exponential functions??PLEASE HELP!!?

im a little stuck on these 3 functions and cant seem to solve them

1. 3^(6-3x)= (1/27)

2. 2^((x^2)-3)=64

if it looks a little complicated its just 2 raised to x squared minus 3 equals 64

3. 9^(2x) * 27^(3-x)= (1/9)

the star is supposed to be a multiplication symbol

5 Answers

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  • Eric
    Lv 4
    1 decade ago
    Favorite Answer

    Q1

    3^(6 - 3x) = 1/27

    3^(6 - 3x) = 3^-3 . . . . <= bases are same, so powers are also same

    Compare:

    6 - 3x = -3

    9 = 3x

    x = 3

    Q2

    2^[(x^2) - 3] = 64

    2^[(x^2) - 3] = 2^6

    Compare:

    x^2 - 3 = 6

    x^2 = 9

    x = ±√9

    x = ±3

    Q3

    9^(2x) × 27^(3 - x) = 1/9

    (3^2)^(2x) × (3^3)^(3 - x) = 3^-2

    3^(4x) × 3^[3(3 - x)] = 3^-2

    3^(4x) × 3^(9 - 3x) = 3^-2

    3^(4x + 9 - 3x) = 3^-2

    3^(x + 9) = 3^-2

    Compare:

    x + 9 = -2

    x = -11

    Done

  • 1 decade ago

    1. x = 3 -- just take log base 3 of both sides and solve the resulting equation.

    2. x = 3. Same as above, except you take log base 2.

    3. x = -11. 9 = 3^2 and 27 = 3^3 -- use this to simplify the equation to 3^(x+9) = 1/9. Take log base 3 and solve.

  • 1) 3^(6 - 3x) = 3^(-3)

    6 - 3x = -3

    -3x = -9

    x = 3

    2) 2^((x^2)-3) = 64

    2^((x^2)-3) = 2^6

    x^2 - 3 = 6

    x^2 = 9

    x = +/- 3

    3) 9^(2x) * 27^(3-x)= (1/9)

    3^(4x) * 3^(3(3-x) = 3^-2

    3^(4x + 3(3 - x)) = -2

    4x + 9 - 3x = -2

    x = -11

  • 1 decade ago

    1. x = 3

    2. x1 = 3 x2 = -3

    3. i GUESS x = -10

    i am quite sure for 1 and 2, but 3 i'm not sure, can't be bothered to get a paper :D

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  • Anonymous
    1 decade ago

    use logs. You are solving equations of exponential functions. You are not solving exponential functions.

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