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# Help with Ranges watch

1. Given
f(x)= e^2x +3
g(x)= ln(x-1)

Find fg and state it's range. I got the to fg being:
(x+1)^2 +3 which is what the answers says
However, I expanded the brackets to get x^2-2x+4. I got the range as fg is greater than or equal to 4 because that's the minimum point of the graph but the answer is fg is greater than 3. Can someone explain why this is?
2. bump
3. (Original post by Year11guy)
Given
f(x)= e^2x +3
g(x)= ln(x-1)

Find fg and state it's range. I got the to fg being:
(x+1)^2 +3 which is what the answers says
However, I expanded the brackets to get x^2-2x+4. I got the range as fg is greater than or equal to 4 because that's the minimum point of the graph but the answer is fg is greater than 3. Can someone explain why this is?
Just because the y intercept is 4 doesn't mean that (0,4) is the minimum point.

Try using your differentiation or complete the square to find the minimum point.
4. (Original post by The_Big_E)
Just because the y intercept is 4 doesn't mean that (0,4) is the minimum point.

Try using your differentiation or complete the square to find the minimum point.
It's okay I figured it out. Thanks for replying anyway.

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