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Derivative help - calculus!?

How do you calculate the derivative of 2^x + 3^x where x = -0.1?

Update:

on paper, without the nice ln() function on the calculator...

4 Answers

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  • 1 decade ago
    Favourite answer

    log(3)*3^x+log(2)*2^x

  • 1 decade ago

    ln(2)*(2^x)+ln(3)*(3^x) is the derivative, just plug in -.1

  • 1 decade ago

    if the value of x is predetermined

    than all you can do is substitute

    the known value into the equation

    2^(-0.1)+3^(-0.1)

    Raise 2 to the -0.1th power.

    0.933+3^(-0.1)

    Raise 3 to the -0.1th power.

    0.933+0.896

    Add 0.896 to 0.933 to get 1.829.

    1.829

    However

    they want you to determine the

    derivative first then plug in the

    x=-0.1

    2^(x)+3^(x)

    The derivative of 2^(x) is 2^(x)*ln(2).

    (d)/(dx) 2^(x)+3^(x)=

    2^(x)*ln(2)+(d)/(dx) 3^(x)

    The derivative of 3^(x) is 3^(x)*ln(3).

    (d)/(dx) 2^(x)+3^(x)=

    2^(x)*ln(2)+3^(x)*ln(3)

    Multiply 2^(x) by ln(2) to get 2^(x)ln(2).

    (d)/(dx) 2^(x)+3^(x)=

    2^(x)ln(2)+3^(x)*ln(3)

    Multiply 3^(x) by ln(3) to get 3^(x)ln(3).

    (d)/(dx) 2^(x)+3^(x)=

    2^(x)ln(2)+3^(x)ln(3)

    The derivative of 2^(x)+3^(x) is

    2^(x)ln(2)+3^(x)ln(3).

    now plug in the -0.1 into x

  • ?
    Lv 4
    1 decade ago

    f(x) = 2^x + 3^x

    f ' (x) = 2^x * ln(2) + 3^x * ln(3)

    so f ' (-0.1) = 2^(-0.1) ln(2) + 3^(-0.1) * ln(3)

    = 1.631

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