If (x+1) and (x-1) are factors of Px3+x2-2x+q then value of p and q are
(a) p = -1, q = 2
(b) p = 2, q = -1
(c) p = 2, q = 1
(d) p = -2, q = -2
Answers
Answered by
0
Answer:
really hard math dont know anything you said for a
Step-by-step explanation:
Answered by
1
Answer:
(b) p=2 and q= —1
Step-by-step explanation:
Let p(x) =px³+x²—2x+q
If x+1 is a factor of p(x), then p(-1)=0
=>p.(—1)³+(—1)²—2.(—1)+q=0
=>—p+1+2+q=0
=>—p+q+3=0
= >q—p= —3 ______i
Similarly, x—1 is also a factor of p(x), then p(1)=0
=>p.(1)³+(1)²—2.1+q=0
=>p+1—2+q=0
=>p+q—1=0
=>p+q=1________ii
Adding equation i and ii,
q+p= 1
q-p= -3
————
2q= - 2
=>q= —2/2= —1
Putting q's value in equation ii,
p+ —1=1
=>p=1+1=2
Let me know if you don't understand any step!
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