Is f (x) = X4 power - 3x2 power + 5 an odd function or even function, non odd non even or both odd and even?

Is f (x) = X4 power - 3x2 power + 5 an odd function or even function, non odd non even or both odd and even?

f(x)=x^4-3x^2+5
F (- x) = f (x), so it is even function

Is the function f (x) = X3 differentiable?
If a point is on the image, how many tangents can it have? (greater than or equal to 1)? What is the tangent of a curve 、、、？

Of course

Find the maximum and minimum values of the function y = 2x3-3x2-12x + 8 in the interval [- 2,3]

From y = 2x & sup3; - 3x & sup2; - 12x + 8
For y, y ′ = 6x & sup2; - 6x-12,
Let y ′ = 0,6x & sup2; - 6x-12 = 0
（x+1）（x-2)=0,
Two stationary points x = - 1, x = 2 are two extreme points,
Find endpoint:
f（-2）=4,f（3）=-1
f（-1）=15,f（2）=-12,
∴ymax=15,ymin=-12.

Given that a > 0, f (x) = X3 ax is a monotone function on [1, + ∞), then the value range of a is ()
A. （3，+∞）B. [3，+∞）C. （-∞，3）D. （-∞，3]

When x ≥ 1, f ′ (x) = 3x2-a ≥ 0, that is, a ≤ 3x2. And the minimum value of 3x2 & nbsp; on [1, + ∞) is equal to 3, so a ≤ 3. So D