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1 vote
For what value of k is the expression x^4 + kx^2+36 a perfect square

A.36
B. 6
C. 72
D. 12

User Aitnasser
by
7.2k points

2 Answers

5 votes

Answer:

B) 6

Explanation:

We need to figure out the value of k in x⁴+kx²+36 -> (x²+a)(x²+b) where a+b=k and ab=36 as a=b. Therefore, k needs to be 6 because 6*6=36 and 6+6=12 given a=b.

User Ahreum
by
8.2k points
5 votes
I think it might be 36
User Olli
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7.5k points