When you multiply a function by -1, what is the effect on its graph?

The graph is reflected about x-axis.

Step-by-step explanation:

Since, rule of reflection across x-axis,

And, the rule of reflection across y-axis,

Thus, when a function f(x) is reflected across x-axis,

Then, the transformed function is -f(x),

While, when f(x) is reflected across y-axis,

The transformed function is -f(x),

Hence, we can say that,

When a function is multiplied by -1, it will reflect about x-axis.

step-by-step explanation:

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