Integrate the function f(x)=3^x+2 with respect to x

First note that a=eln(a) and ln(ab)=bln(a)By substituting a=3x we get a=3x=eln(3^x)=exln(3), and hence f(x)=exln(3)+2∫ f(x)dx=∫ exln(3)+2 dx . First we can split this into the sum of two integrals ∫ exln(3)dx + ∫ 2 dxRemember that d/dx(eg(x)) for some function g is equal to g'(x)eg(x) by the chain rule so ∫ exln(3)dx must equal 1/ln(3)exln(3) as 1/ln(3)d/dx(xln(3))=1/ln(3)ln(3)=1And ∫ 2 dx is solved by simply raising the power of any x elements by 1 and dividing the coefficient by this raised power. Hence ∫ 2 dx=2/1x0+1=2x=2xSo ∫ f(x)dx=(1/ln(3)exln(3))+2x+c (remembering the constant) and by the previous substitution 3x=ex*ln(3) ∫ f(x)dx=1/ln(3)*3x+2x+c

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