Yes. Because it is in second degree. but i confuse because it havent have the form ax2+bx+c=0
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Yes. It can be considered as a quadratic function because the quadratic function is defined by the equation ax2+bx+c. the highest value of the exponent in a quadratic function is 2. Since the highest exponent of the given is 2, it can be called as quadratic function. Even if its not in the ax^2+bx+c=0 form.

Not sure but hope I helped.