52458512
Evaluate each definite integral.
a) \(\int_{-2}^{4}(x+1)\,dx\)
b) \(\int_{0}^{5}(2-0.8t)\,dt\)
c) \(\int_{4}^{1}(1.5u-3)\,du\)
Hints
- Find an antiderivative of each integrand.
- Substitute the upper and lower limits carefully.
- Pay special attention when the upper limit is less than the lower limit.
- Integrate each term separately.
Solution
1. For a), an antiderivative is \(F(x)=\frac{1}{2}x^2+x\). Thus, \(F(4)-F(-2)=12-0=12\).
2. For b), an antiderivative is \(F(t)=2t-0.4t^2\). Thus, \(F(5)-F(0)=10-10=0\).
3. For c), an antiderivative is \(F(u)=0.75u^2-3u\). Thus, \(F(1)-F(4)=-2.25-0=-2.25\).
Answer
a) \(12\)
b) \(0\)
c) \(-2.25\)
