document.write( "Question 1010200: Need help with one more please:
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document.write( "Differentiate as many times as necessary to evaluate f'''(-3) if f(x) = 2 ln( absolute value of x) \n" );
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Algebra.Com's Answer #625664 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! f(x) = 2 * ln(|x|) \n" ); document.write( "*************************************************************************** \n" ); document.write( "Calculate the first derivative of f(x) \n" ); document.write( "d/dx(f(x)) = d/dx(2 log(abs(x))) \n" ); document.write( "The derivative of f(x) is f'(x): \n" ); document.write( "f'(x) = d/dx(2 log(abs(x))) \n" ); document.write( "Factor out constants: \n" ); document.write( "f'(x) = 2 d/dx(log(abs(x))) \n" ); document.write( "Using the chain rule, d/dx(log(abs(x))) = ( dlog(u))/( du) ( du)/( dx), where u = abs(x) and ( d)/( du)(log(u)) = 1/u: \n" ); document.write( "f'(x) = 2 (d/dx(abs(x)))/(abs(x)) \n" ); document.write( "The derivative of abs(x) is x/(abs(x)): \n" ); document.write( "f'(x) = (2 x/(abs(x)))/(abs(x)) \n" ); document.write( "Simplify the expression: \n" ); document.write( "f'(x) = (2 x)/abs(x)^2 \n" ); document.write( "Simplifying powers, abs(x)^2 = x^2: \n" ); document.write( "f'(x) = 2/x \n" ); document.write( "***************************************************************************** \n" ); document.write( "Calculate the second derivative of f(x) \n" ); document.write( "f'(x) = 2/x \n" ); document.write( "d/dx(f'(x)) = d/dx(2/x) \n" ); document.write( "The second derivative of f'(x) is f''(x): \n" ); document.write( "f''(x) = d/dx(2/x) \n" ); document.write( "Factor out constants: \n" ); document.write( "f''(x) = 2 d/dx(1/x) \n" ); document.write( "Use the power rule, d/dx(x^n) = n x^(n-1), where n = -1: d/dx(1/x) = d/dx(x^(-1)) = -x^(-2): \n" ); document.write( "f''(x) = 2 (-1)/(x^2) \n" ); document.write( "Expand the left hand side: \n" ); document.write( "f''(x) = -2/x^2 \n" ); document.write( "***************************************************************************** \n" ); document.write( "Calculate the third derivative of f(x) \n" ); document.write( "f''(x) = -2/x^2 \n" ); document.write( "The third derivative of f(x) is f'''(x): \n" ); document.write( "f'''(x) = d/dx(-2/x^2) \n" ); document.write( "Factor out constants: \n" ); document.write( "f'''(x) = -2 d/dx(1/x^2) \n" ); document.write( "Use the power rule, d/dx(x^n) = n x^(n-1), where n = -2: d/dx(1/x^2) = d/dx(x^(-2)) = -2 x^(-3): \n" ); document.write( "f'''(x) = -2 (-2)/x^3 \n" ); document.write( "Simplify the expression: \n" ); document.write( "f'''(x) = 4/x^3 \n" ); document.write( "Expand the left hand side: \n" ); document.write( "f'''(x) = 4/x^3 \n" ); document.write( "**************************************************************************** \n" ); document.write( "evaluate \n" ); document.write( "f'''(-3) = 4 / (-3)^3 = -4 / 27 = -0.148148148 approx -0.15 \n" ); document.write( " \n" ); document.write( " |