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At which x value will f(x)=3x+3 exceed g(x)=3x+10

2 Answers

3 votes
there are no x value that allows f(x) to exceed g(x). f(x) is parallel to g(x) and it will always be 7 less than g(x).
User VKen
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0 votes
We write an inequality:


f(x) > g(x)


3^x + 3 > 3x + 10


3^x > 3x + 7

This equation cannot be solved using trivial methods found in high-school classes, so we resort to graphical examination.
3x+7 is a linear function while
3^x is an exponential one (with limit zero as
x approaches
- \infty). We see that
3^x = 3x+7 at approximately
x=2.4 and
x=-2.3.

Indeed, using a computer algebra system such as the ones on modern TI calculators and on many internet sites gives equality at
x=2.42, -2.31. By observing our graph, we see that
f(x) > g(x) when
x > 2.42 or
x < -2.31.
User VPP
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6.3k points