Engineering Board Exam Reviewer · Definite Integrals · medium
Evaluate: 0∞dx/x2+4x+13
- ≤ft(3/2 )3 0.328
- ≤ft(2/3 )3 0.196
- π/6 0.524
- ≤ft(3/2 ) 0.983
Answer
A. ≤ft(3/2 )3 0.328
Solution
Complete the square: x2+4x+13=(x+2)2+9. Then ≤ft[ 13 +2/3 ]0∞= 13≤ft( π2- 23 )= 13 32 0.328.