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2 votes
Find all the zeros of the equation.

-3x^4 + 27x^2 + 1200 = 0

User Joe Lyga
by
7.2k points

2 Answers

4 votes

Answer:

The answer is 5,-5,4i,-4i.

Explanation:

When the equation is divided by -3 it becomes:


x^4-9*x^2-400=0

If we factorize the equation, the equation will become as:


(x+5)*(x-5)*(x^2+16)=0

That means the equation has 2 real zeros.


x=5\\x=-5

Also it has 2 complex zeros also. Those are:


x=-4i\\x=4i

User Panomosh
by
7.8k points
5 votes

-3x^4 + 27x^2 + 1200 = 0

factor out -3

-3(x^4 -9x^2 -400)=0

divide by -3

x^4 -9x^2 -400=0

(x^2-25) (x^+16) = 0

x^2-25=0 x^2+16=0

(x-5)(x+5)=0 x^2=-16

x=5 x=-5 x = 4i x=-4i

Answer: x=5 x=-5 x = 4i x=-4i



User Daniel Greaves
by
7.0k points