Q. 25 Check whether (x+1) is a factor of 2x²-x-1
Answers
Answer:
To check this we have to divide the the factor that is x+1 by the given polynomial that is
We can perform this division by the following method which is shown in attachment and can see whether it is factor of the given polynomial or not .
On dividing by this factor if we get the remainder is equal to zero then we will conclude that it is a factor and if not get remainder as zero then it is not the factor of given polynomial .
See the attachment.
➭ (X + 1) is not a factor of 2x² - x - 1
Because Reminder ≠ 0 and it is 2 .
If on diving the given factor we get reminder as 0 we can say that the number is divisible by the given polynomial.
Another Way :-
x -1 = 0
⇒ x = -1
Put Value of x in equation
We have,
2(-1)² - (-1) -1
⇒ 2(1) + 1 - 1
⇒ 2
So, 2x² - x - 1 is not divisible by (x+1)
Because it is ≠ 0
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Hope it helps.