Im giving you instrutions to get the answer its simple:D
The figure above shows a circular sector OAB<span> , subtending an </span>angle<span> of θ radians ... The points A and B lie on the circle so that the </span>angle AOB<span> is 1.8 radians. .... c) </span>Calculate<span> the smallest </span>angle<span> of the </span>triangle<span>ABC , giving the answer in </span>degrees<span>, .... Given that the length of the arc AB is </span>48<span> cm , </span>find<span> the area of the shaded region</span><span>.
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Notice how points T and Z are vertically aligned, or vertically lined up. This is where the graph fails the vertical line test.
The input x = 2 leads to the outputs y = 3 and y = 5 (which are the y coordinates of points Z and T in that order).
A function is only possible when any given input leads to <u>exactly one</u> output only. It would be like saying "the conversion function from Celsius to Fahrenheit has 0 degrees C convert to both 32 degrees F and 50 degrees F at the same time". But such a statement makes no sense and it's not useful. So this is one example of why having one output makes sense for a function.
In short, we need one output for any given input. But the input x = 2 leads to more than one output. That's why we don't have a function.