Step 1: Evaluate the definite integral.
The integral to evaluate is β«1pβ(pxβ1)dx.
First, find the antiderivative of pxβ1 with respect to x:
β«(pxβ1)dx=p2x2ββx+C
Now, apply the limits of integration from 1 to p:
[2px2ββx]1pβ=(2p(p)2ββp)β(2p(1)2ββ1)
=(2p3ββp)β(2pββ1)
=2p3ββpβ2pβ+1
Combine the terms involving p:
=2p3ββ22pββ2pβ+1
=2p3ββ23pβ+1
Step 2: Set the evaluated integral equal to 0.
We are given that β«1pβ(pxβ1)dx=0.
So, we set the expression from Step 1 to 0:
2p3ββ23pβ+1=0
Multiply the entire equation by 2 to eliminate the denominators:
p3β3p+2=0
Step 3: Solve the cubic equation for p.
We look for integer roots by testing divisors of the constant term (2), which are Β±1,Β±2.
Test p=1:
(1)3β3(1)+2=1β3+2=0
Since p=1 satisfies the equation, (pβ1) is a factor of the polynomial.
We can use polynomial division or synthetic division to find the other factors. Using synthetic division with root 1:
1 | 1 0 -3 2
| 1 1 -2
----------------
1 1 -2 0
The quotient is p2+pβ2.
So, the cubic equation can be factored as:
(pβ1)(p2+pβ2)=0
Now, factor the quadratic term p2+pβ2. We need two numbers that multiply to -2 and add to 1. These numbers are 2 and -1.
p2+pβ2=(p+2)(pβ1)
Substitute this back into the factored cubic equation:
(pβ1)(p+2)(pβ1)=0
(pβ1)2(p+2)=0
Step 4: Determine the values of p.
From (pβ1)2=0, we get pβ1=0, which means p=1.
From (p+2)=0, we get p=β2.
Thus, the values of p are 1 and β2.
The final answer is p=1,p=β2β.
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