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Why do you use -b over 2a to find the x-value of the vertex of a parabola?
Wiki User
∙ 12y ago
f (x) = ax² + bx + c
f ` (x) = 2ax + b = 0 for turning point
2ax = - b
x = - b / 2a as required
Wiki User
∙ 12y ago
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What is a platonic solid and how many are there and what are their names?
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How do you find the vertex of an absolute value function?
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A regular pyramid has a base and vertex over the center of the base?
A regular pyramid has a regular polygon base and a vertex over the center of the base. By:Cherrylvr :)
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Apex, or vertex
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From the quadratic formula, the zeros (where y=0) is -b/(2a) +/- sqrt(b^2 -4ac)/(2a). The expression inside the square root is known as the descriminant. Being that the parabola is symmetric, one of the zeros will be at the vertex + sqrt(b^2 -4ac)/(2a) and the other zero is at vertex - sqrt(b^2 -4ac)/(2a). The vertex is halfway between these two values, so the x coordinate of the vertex is -b/(2a). Or if you use Calculus, you can take the derivative of f(x) = ax^2 + bx + c. f'(x) = 2ax + b. Set equal to zero and solve for x. x = -b/(2a).
Can the graph of a polynomial function have no x-intercept?
Yes, over the real set of numbers. For example, the graph of y=x2+1 is a regular parabola with a vertex that is one unit above the origin. Because the vertex is the lowest point on the graph, and 1>0, there is no way for it to touch the x-axis.NOTE: But if we're considering imaginary numbers, the values "i" and "-i" would be the zeroes. I'm pretty sure that all polynomial functions have a number of zeroes equal to their degree if we include imaginary numbers.
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x=-b/2a [negative B over 2A]
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A thrown basketball follows a path that can be approximated by a parabola. The approximation ignores air resistance and any curve imparted by spin on the ball. Over the distances involved, both are likely to be negligible.
A has a regular polygon base and a vertex over the center of the base?
regular pyramid
A regular pyramid has a base and a vertex over the center of the base?
Regular Polygon...
A regular pyramid has a regular polygon base and a what over the center of the base?
vertex
Does a regular pyramid have a regular polygon as its base and a vertex over the base's center?
Yes
A regular pyramid has a regular polygon as its base and vertex over the base's center?
Yes.
