plz.solve the question no. 11
Answers
Answer:
-3 and -1
Step-by-step explanation:
two of the zeroes are (root 5) & (-root 5).
the degree of the equation x4+4x3-2x2-20x-15 is 4. So, there will be four zeroes.
x = (root 5) , x = (-root 5)
=> (x - root 5)(x + root 5)
= (x)sq. - (root 5)sq.
= x2-5
then, you have to divide the equation by the above expression.
Sorry, I can not show you the full division process because I don't know how to show equations here. But I have written the answer below :-
x sq.+4x+3
Now you have to factorize the above expression -
x sq.+4x+3
=> x sq.+x+3x+3
= x(x+1)+3(x+1)
= (x+1)(x+3)
then, do like this :-
x+1 = 0 | x + 3 = 0
or, x = -1 | or, x = -3
therefore, all the zeroes of the given polynomial are (root 5), (-root 5), -1 and -3.
Hope, it will help you....