Question

Which exponential function goes through the points (1, 16) and (4, 128)?

f(x) = 4(4)x

f(x) = 8(2)x

f(x) = 8(2)-x

f(x) = 4(4)-x

Answer 1

I think its B am I right?

Answer 2

@darkside3704 @quetejedi @QueenBee232 @Rina.r @ash2326

Answer 3

@cutecupcake

Answer 4

you are correct :)

Answer 5

could you show me how to solve it thanks my brother gave me the answer but doesn't have the patience to teach me

Answer 6

haha yeah sure
you start with general exponential function
\[y = a(b^x)\]
plug in the given points for x,y
\[a*b = 16\]
\[a*b^4 = 128\]
solve for a,b by substitution
from 1st equation, solve for a
\[a = \frac{16}{b}\]
sub into 2nd equation
\[\frac{16}{b}*b^4 = 128\]
solve for b
\[16b^3 = 128\]
\[b^3 = 8\]
\[b = 2\]
plug back in to get a
\[a = \frac{16}{2} = 8\]
\[y = 8(2^x)\]

Answer 7

woaah :O

Answer 8

thankyou can you help me solve another one?

Answer 9

ok

Answer 10

The table below shows the values of f(n) for different values of n.



n 1 2 3 4 5 6
f(n) 1 2 5 12 29 70


Which recursive function best represents the values shown in the table?
f(1) = 1, f(2) = 2, f(n) = 2f(n -1) f(n - 2); n > 2

f(1) = 1, f(2) = 2, f(n) = f(n -3) + f(n - 2); n > 2

f(1) = 1, f(2) = 2, f(n) = 2f(n -1) + f(n - 2); n > 2

f(1) = 1, f(2) = 2, f(n) = f(n -3) f(n - 2); n > 2

Answer 11

I think its c

Answer 12

i agree

Answer 13

yep its c

f(n-3) is impossible since f(0) is not defined

Answer 14

chief ur doing good :)

Answer 15

he function below shows the relationship between the length of each side of a square (y) and the area of the square (x+2).

Which graph best shows the function?