Find the integral of 3x^2 + 4x + 9 with respect to x.

We must first remember that to integrate, we must increase the power by 1 and divide by this new power.

Therefore, to integrate 3x^2 + 4x + 9, we take the first term, 3x^2. Using the above method, we find that the integral of this is (3x^3)/3 = x^3.

Taking the second term, 4x, we find the integral to be (4x^2)/2 = 2x^3.

Taking the final term, 9, we find the integral to be (9x)/1 = 9x.

As the question gives an indefinite integral (an integral without any limits) we must also remember to add a constant, which we can call C.

Therefore, the integral of 3x^2 + 4x + 9 with respect to x is 2x^2 + x^3 + 9x + C.

DJ

Related Maths A Level answers

All answers ▸

a) Solve the following equation by completing the square: x^(2)+ 6x + 1= 0. b) Solve the following equation by factorisation: x^(2) - 4x - 5 = 0 c) Solve the following quadratic inequality: x^(2) - 4x - 5 < 0 (hint use your answer to part b)


How do I integrate log(x) or ln(x)?


f(x) = x^3+2x^2-x-2 . Solve for f(x) = 0


A geometric progression has first term 3 and second term -6. State the value of the common ratio.