Which of the quadratic functions has the narrowest graph? y = 1/2x^2

Which of the quadratic functions has the narrowest graph? y = 1/2x^2 or y = 4x^2 or y = 1/7x^2 or y = 2x^2

Answer:

All these functions are obtained from transforming a function y=x2. When we multiply a function by a scalar c it is stretched vertically when c>1 and compressed when c<1.

This means that the function is narrowest for the greatest scalar c.

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So, quadratic function y=4x2 has the narrowest graph.