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@sammixboo
@Shadow
is it +10 +11 +12+13+14+15 etc.
@dude
Do you know how to write an exponential function?
no
The form looks like this: \[f(x) = ab ^{x} \] Where a is our starting value, and b is our common ratio between our y values. Our starting value is the number in the set of y values that corresponds with x at zero. Can you identify the starting value?
100?
Correct.
Now as for our common ratio, there is a simple way to discover it. Simple look at our y values. We have 100, 110, and 121. Use this formula. \[b = \frac{ y _{2} }{ y _{1}}\] Remember that b is our common ratio between our y values. You can solve for this by dividing any number in the our set of y values, by the number that came before it. This gives us the number by which you multiply, to get the next number.
so 110 / 100?
Does that make sense?
Correct
1.1
You have a and b, can you put the exponential function together now?
f(x)=100 x 1.1?
Close \[f(x) = 100(\frac{ 11 }{ 10 })^{x} \] or \[f(x) = 100(1.1)^{x} \] Some teachers may prefer it in fraction form.
is the x the year ?
Now that we have our exponential function, try input any x value (years) into our x, and solve for an output (which would give us the number of trucks registered in a year).
ok
990? if it is 9 years
Remember that we are taking it to the power of x, not multiplying it by x.
\[1^3 = 1 \times 1 \times 1 \neq 1 \times 3\]
oops XD
235.794769
Correct :)
236 for rounding
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