document.write( "Question 1202652: Given f(x) = x^2 +3, find and simplify the difference quotient ([f(x+h) - f(x)])/h.\r
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document.write( "What is the best way to go about solving this? I know I need to substitute the equations together like (x+h)^2 + 3 - (x^2=3)\r
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document.write( "I don't know if that substitution is correct. Any help with this problem would be greatly appreciated.
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Algebra.Com's Answer #837601 by Theo(13342)![]() ![]() You can put this solution on YOUR website! i believe it works like this.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you want the limit of (f(x + h) - f(x)) / h as h approaches 0.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your equation if f(x) = x^2 + 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f(x+h) is derived by replacing x with (x + h) in the original equation to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f(x+h) = (x+h)^2 + 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "simplify this to get f(x+h) = x^2 + 2hx + h^2 + 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(f(x + h) - f(x)) / h becomes (x^2 + 2hx + h^2 + 3 - (x^2 + 3)) / h which becomes:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x^2 + 2hx + h^2 + 3 - x^2 - 3) / h\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "combine like terms to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2hx + h^2 / h\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "h from the numerator and the denominator cancel out and you are left with:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "2x + h\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "as h approaches 0, this becomes 2x.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that's your derivative.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the results from the derivative calculator at https://www.derivative-calculator.net/ confirm that the derivative is 2x.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the derivative is the same as the limit of [f(x+h) - f(x)] / h, as h approaches 0.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "let me know if you still have any questions regarding this.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "theo\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |