Question

plz.solve the question no. 11​

Answer 1

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....