Pls help me on this one
1 answer:
You might be interested in
Answer:
- after week 7: 4374 pennies
- 486 pennies: after week 5
Step-by-step explanation:
The sequence values have a first term of 6 and a common ratio of 3, so can be described by the formula ...
an = 6·3^(n-1)
This can be rearranged to ...
an = 2·3^n
__
When n=7, the value is ...
a7 = 2·3^7 = 4374 . . . . pennies saved after 7 weeks
__
To find when there are 486 pennies saved, we can solve the equation ...
486 = 2·3^n
243 = 3^n
log(243) = n·log(3) . . . . . . . take the logarithm
log(243)/log(3) = n = 5 . . . . divide by the coefficient of n
Tabitha will have saved 486 pennies after 5 weeks.
To find the inverse of a function, replace every x in the equation with a y, and replace every y in the equation with an x:
Add 9 to both sides:
Square root both sides to get y by itself:
This equation can be simplified by taking the square root of 9 out of the root:
The inverse of this function is y = 3 + √x.
Add 9 to both sides:
Square root both sides to get y by itself:
This equation can be simplified by taking the square root of 9 out of the root:
The inverse of this function is y = 3 + √x.