SOLUTION: find the formula for an exponential function that passes through (-1,4/3) and (4,324)

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Question 1127673: find the formula for an exponential function that passes through (-1,4/3) and (4,324)
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
model for y=a%2Ab%5Ex

Plug in the point coordinates
system%28ab%5E%28-1%29=4%2F3%2Ccross%28ab%5E4=304%29%2Cab%5E4=324%29

%28ab%5E4%29%2F%28ab%5E%28-1%29%29=324%2F%284%2F3%29

b%5E5=%283%2A324%29%2F4

cross%28b%5E5=228%29
b%5E5=243

cross%28b=2.96201%29
highlight%28b=3%29

Using either original equations, highlight_green%28a=4%29.


Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.

            Since the solution by @gosgarithmetic contains a lot of errors,  giving the wrong answers   highlight_green%28b=2.96201%29  and   highlight_green%28a=3.9493%29,
            I came to fix it.

            Find my correct solution below.

            And ignore that of  @josgarithmetic,  for your safety. 


y = a%2Ab%5Ex


Plug in the point coordinates

system%28ab%5E%28-1%29=4%2F3%2Cab%5E4=324%29


%28ab%5E4%29%2F%28ab%5E%28-1%29%29 = 324%2F%284%2F3%29


b%5E5 = %283%2A324%29%2F4


b%5E5 = 3*81 = 3%5E5


highlight_green%28b=3%29


Using either original equations,  highlight_green%28a=4%29.


Answer.  y = 4%2A3%5Ex.

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Regarding @josgarithmetic, this person is VERY well known  (or better to say,  very badly known,  unfortunately)  in this forum,
for his inability to solve problems correctly and to make calculations accurately.


So be very careful when you obtain "solutions" from him.

In half of all cases  (if not at most cases)  they are wrong.

Do not trust him and always wait for reaction of other tutors.


In the normal school environment he would be fired in the second day.


I think about thousands of visitors and students who do understand almost nothing in Math and who were misguided
by his false and wrong quasi- and pseudo-"solutions".


People,  be careful about  @josgarithmetic  !   !    !