document.write( "Question 1171448: ``The value of function -10000e^(-0.03x)-120x+10000 at its critical points is \n" ); document.write( "
Algebra.Com's Answer #850928 by CPhill(1959)\"\" \"About 
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To find the value of the function at its critical points, we need to:\r
\n" ); document.write( "\n" ); document.write( "1. **Find the derivative of the function.**
\n" ); document.write( "2. **Set the derivative equal to zero and solve for x.** This will give us the critical points.
\n" ); document.write( "3. **Plug the critical points back into the original function to find the function's value.**\r
\n" ); document.write( "\n" ); document.write( "Let's do this step-by-step:\r
\n" ); document.write( "\n" ); document.write( "**1. Find the derivative:**\r
\n" ); document.write( "\n" ); document.write( "The given function is:\r
\n" ); document.write( "\n" ); document.write( "f(x) = -10000e^(-0.03x) - 120x + 10000\r
\n" ); document.write( "\n" ); document.write( "The derivative, f'(x), is:\r
\n" ); document.write( "\n" ); document.write( "f'(x) = -10000 * (-0.03) * e^(-0.03x) - 120
\n" ); document.write( "f'(x) = 300e^(-0.03x) - 120\r
\n" ); document.write( "\n" ); document.write( "**2. Set the derivative to zero and solve for x:**\r
\n" ); document.write( "\n" ); document.write( "300e^(-0.03x) - 120 = 0
\n" ); document.write( "300e^(-0.03x) = 120
\n" ); document.write( "e^(-0.03x) = 120 / 300
\n" ); document.write( "e^(-0.03x) = 0.4\r
\n" ); document.write( "\n" ); document.write( "Take the natural logarithm of both sides:\r
\n" ); document.write( "\n" ); document.write( "ln(e^(-0.03x)) = ln(0.4)
\n" ); document.write( "-0.03x = ln(0.4)
\n" ); document.write( "x = ln(0.4) / -0.03
\n" ); document.write( "x ≈ 30.543\r
\n" ); document.write( "\n" ); document.write( "**3. Plug the critical point back into the original function:**\r
\n" ); document.write( "\n" ); document.write( "f(x) = -10000e^(-0.03x) - 120x + 10000
\n" ); document.write( "f(30.543) = -10000e^(-0.03 * 30.543) - 120 * 30.543 + 10000
\n" ); document.write( "f(30.543) = -10000e^(-0.91629) - 3665.16 + 10000
\n" ); document.write( "f(30.543) = -10000 * 0.4 + 6334.84
\n" ); document.write( "f(30.543) = -4000 + 6334.84
\n" ); document.write( "f(30.543) = 2334.84\r
\n" ); document.write( "\n" ); document.write( "**Therefore, the value of the function at its critical point is approximately 2334.84.**
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