Help with this calc question?

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1 Answer
Feb 8, 2018

Option #B#, which is #18#, will be correct.

Explanation:

One of the properties of definite integrals states that

#int_a^cf(x)dx= int_a^bf(x)dx + int_b^cf(x)dx# if #a ≤ b ≤ c#

We can apply that to this problem. We know that

#int_2^8g(x) dx = int_2^6 g(x)dx+ int_6^8g(x)dx#

Two of the integral values are known, it's just a matter of solving for the third.

#13 = int_2^6 g(x)dx - 3#

#16 = int_2^6g(x)dx#

Now add the constant.

#2 + 16 = 18#

Hopefully this helps!