Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.

?
Lv 4
? asked in Education & ReferenceHomework Help · 7 years ago

Needing help with exponential function problems?

4^x * 2^(x^2)=16^2

3^(x^3)=9x

8^(-x+14)=16^x

e^x=e^(3x+8)

Update:

Yes it is 9^x. My apologies. Thanks

1 Answer

Relevance
  • 7 years ago

    1 4^x * 2^(x^2)=16^2

    (2^2)^x * 2^(x^2) = (2^4)^2............expressing 4 and 16 as powers of 2

    2^(2x) * 2^(x^2) = 2^(8)

    2^(2x + x^2) = 2^(8) ................ law of indices for multiplication

    2x + x^2 = 8 ...............powers of the same base

    x^2 + 2x - 8 = 0

    (x + 4)(x - 2) = 0.................factorising

    x = 2, - 4

    2 3^(x^3)=9x ....... Is this suppose to be 3^(x^3) = 9^x?

    3^(x^3) = (3^2)^x .........expressing 9 as powers of 3

    3^(x^3) = 3^(2x)

    x^3 = 2x

    x^3 - 2x = 0

    x ( x^2 - 2) = 0

    x = 0, +/-sqrt(2)

    3 8^(-x+14)=16^x

    (2^3)^(-x + 14) = (2^4)^x ................ 8 = 2^3, 16 = 2^4

    2^(-3x + 42) = 2^4x ................ power of power rule of exponents

    - 3x + 42 = 4x ........................ If a^m = a^n, then m = n

    42 = 7x

    x = 6

    4 e^x=e^(3x+8)

    x = 3x + 8....................... If a^m = a^n, then m = n

    - 2x = 8

    x = - 4

    Hope I made your day

Still have questions? Get your answers by asking now.