Ask your own question, for FREE!
Mathematics 6 Online
jknkjkjnjjjkl:

math problem

jknkjkjnjjjkl:

jknkjkjnjjjkl:

@snowflake0531

jknkjkjnjjjkl:

@florisalreadytaken

jhonyy9:

exponential function form \(f(x) = a^x\)

Florisalreadytaken:

is it not \[ f(x) = a \times b^x\] ?

jknkjkjnjjjkl:

whos right

Florisalreadytaken:

following the one Andreas suggested, it will be a very long and hard t understand explanation lol -- so lets go with mine -- lowe me a moment to write it down

jknkjkjnjjjkl:

alright

NRG:

\[y=a(b)^x\]

Florisalreadytaken:

so, an exponential function is in the form of: \( y = a \times b^x \) we are given: \[ x=2 \; ; \; y=-12 \] and \[ x=3 \; ; \; y=-24 \] for the first one we have: \[ -12= a \times b^2 \] \[ a= \frac{-12}{b^2} \] looking at the first equation, we plug ^ that in for \(a\): \[ y=(\frac{-12}{b^2}) \times b^x \]

jknkjkjnjjjkl:

I simplify y=(-12/b^2)*b^x

jknkjkjnjjjkl:

1

Florisalreadytaken:

nono. substitue the coordinates of the 2nd point, and then solve for b: \[ -24=(\frac{-12}{b^2}) \times b^3 \] do the math

jknkjkjnjjjkl:

im not sure

jknkjkjnjjjkl:

b = 2

Florisalreadytaken:

ahh my whole latex went in the bin๐Ÿ˜ญ๐Ÿ˜‚ -- but yes, \( b=2 \)

Florisalreadytaken:

do you remember \( a= \frac{-12}{b^2} \)? now we can fully solve for a. \[ a= \frac{-12}{2^2} \] \[ \underline{a=-3} \]

Florisalreadytaken:

so we have \[ a=\color{lightskyblue}{-3} \] and \[ b=\color{tomato}{2} \]

jknkjkjnjjjkl:

Florisalreadytaken:

what? noooo

Florisalreadytaken:

plugging that info in the formula, we get \[ \Large f(x) = \color{tomato}{2} \times \color{lightskyblue}{ -3}^x \] \[ \updownarrow \] \[ \Large f(x) = \color{tomato}{2} \times \color{lightskyblue}{( -3)}^x \]

jknkjkjnjjjkl:

thanks

Florisalreadytaken:

you got it!

jknkjkjnjjjkl:

Florisalreadytaken:

oh, maybe the \( \times \) sign is not necessary

jknkjkjnjjjkl:

Florisalreadytaken:

that doesnt make sense :\ -- and you missed the exponential \(x\) in your answer

jknkjkjnjjjkl:

lol

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!