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3 years ago

The roots of the equation x^3+ax^2+bx+c=0 are 1,3 and 3. Show that c= -9 and find the value of a and of b.

Mathematics

1 answer:

KonstantinChe [14]3 years ago

4 0

Answer:

If the equation's roots are 1 , 3, 3 then the equation can be formed by multiplying

(x -1) * ( x - 3) * (x-3) =0

x^2 -6x + 9 * (x -1) equals

x^3 -6x^2 +9x -x^2 + 6x -9 = 0 equals

x^3 -7x^2 + 15x -9 = 0

cubic equations GENERALLY have the form

ax^3 +bx^2 + cx +d = 0

Therefore

a =1 b = -7 c = 15 and d = -9

So, to make the numbers equal the equation in the problem:

x^3 + ax^2 + bx + c = 0

a = -7 b = 15 and c = -9

Step-by-step explanation:

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