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C3 domain and range

Lilly1234567890

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I need help in part c.

Shouldn't it be range= any number on y- axis because the domain is XER

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Reply 1

pineneedles

Original post by Lilly1234567890

I need help in part c.

Shouldn't it be range= any number on y- axis because the domain is XER

Posted from TSR Mobile

The equation I got for gf^-1(x) was (3/4)x^2 + 2
If you think about what this graph looks like, it's a quadratic which is shallower than x^2 and it has been translated two units upwards.
This means, regardless of what value you use for x, gf^-1(x) can only ever be equal to or greater than two.
It really helps if you sketch a little graph for these, that's what my teacher always tells me.