document.write( "Question 999361: Very confused on taking antiderivatives. In my class I am not allowed to use integrals, just math logical to solve this problem: e^(x/5) + sin(3x). I know it's sort of like figuring out what the function must have been before the derivative was taken but this keeps giving me trouble. I have to reverse the derivative and get it back to its original state. sin(3x) is simple enough for it to be +sin(3x) it must be a negative cosine and something for which cancels the 3 out so 1/3 therefore, -1/3cos(3x) would be the original. But the original of e^(x/5) this one baffles me. It's really the (x/5) that I don't get. How does undoing that work exactly? what must I do/understand first before getting its antiderivative/\r
\n" );
document.write( "\n" );
document.write( "Thank you! \n" );
document.write( "
Algebra.Com's Answer #617035 by stanbon(75887)![]() ![]() ![]() You can put this solution on YOUR website! f'(x) = e^(x/5)dx \n" ); document.write( "Find f(x) \n" ); document.write( "----- \n" ); document.write( "Let x/5 = u \n" ); document.write( "Then du = (1/5)dx \n" ); document.write( "dx = 5du \n" ); document.write( "----- \n" ); document.write( "dy = e^u(5du) \n" ); document.write( "--- \n" ); document.write( "dy = 5e^u du \n" ); document.write( "-- \n" ); document.write( "Integrate to get: \n" ); document.write( "y = 5e^u \n" ); document.write( "--- \n" ); document.write( "Substitute to get: \n" ); document.write( "y = 5e^(x/5) \n" ); document.write( "------- \n" ); document.write( "Cheers, \n" ); document.write( "Stan H. \n" ); document.write( "----------- \n" ); document.write( " |