Question
In the open interval (0, 1), the polynomial p(x) = x4 - 4x3 + 2 has
Options :
Two real roots
One real root
Three real roots
No real roots
Answer :
One real root
Solution :
Given polynomial, p(x) = x4 - 4x3 + 2
Using intermediate value theorem,
p(0) = 0 - 0 + 2 = 2 p(1) = 1 - 4 + 2 = -1
Since, p(0) > 0 .... (1)
p(1) < 0 .... (2)
From equation (1) and (2),
there exist a value 'x' in between 0 and 1
where, p(x) = 0
Hence, in the open interval (0, 1), the polynomial p(x) has one real root.
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