21Please, do you mean p a + pb +pc + pd
Let P(x) = x^{6}-x^{5}-x^{3}-x^{2}-x
Q(x) = x^{4}-x^{3}-x^{2}-1
If a,b,c,d are roots of q(x) then find the value of P(a)+P(b)+P(d) ?
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11 Answers
11Do, we have to find the answer in terms of a, b, c, d. I'm getting a long expression with the help of brute force.
1arnab is right, it should be P(a)+P(b)+P(c)+P(d)
P(x) = Q(x)(x2+1)+x2-x+1
=> ΣP(a) = Σa2-a+1
=> which can be easily found by using vieta's
=> im getting the answer as 6
71@Risabh.. It is okay for what it isn't asked.
Anyways, I seem to get 3 as answer, But I don't know the correct answer, so may be you people help.
71I just assumed that one obvious root of q(x) i.e., -1 is equal to c. I thought so because it is not given that which are complex or which are real, and order also doesn't matters. So it can well be assumed?
This will easily yield the answer 3.
This was an integer type question. So it think they might have tricked us into something like this