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#1
If f is inversely proportional to g² and f = 8 when g = -2, what is f when g = 4?

I don't understand inverse proportinality, someone please teach me!!

Thanks. 0
4 years ago
#2
(Original post by Awais_)
If f is inversely proportional to g² and f = 8 when g = -2, what is f when g = 4?

I don't understand inverse proportinality, someone please teach me!!

Thanks. 2.

Isn't new years eve mathematics spectacularly fun?
0
#3
(Original post by qwertzuiop)
2.

Isn't new years eve mathematics spectacularly fun?
Haha yup, if I want to change my C grade to an A* grade I need to do Math all year round. 0
4 years ago
#4
|g| is twice as big so g^2 is four times as big... So f is 4 times smaller (divide by 4, inversely proportional).
0
4 years ago
#5
Hey! Let me give you a simple example.
When a is proportional to b,
a=kb, where k is a constant(you can put any random letter)
Then plug in the values you have for a and b and find k. Then use that k value for what you need to calculate.

When a is inversely proportional to b,
then a is proportional to 1/b(as you are getting the inverse of b)
which implies that a=k/b, where k is a constant
Then plug in the values of a and b and find k. Then use the k value for further calculations.

Back to your question...if f is inversely proportional to g^2,
then f is proportional to the inverse of g^2 (i.e. 1/g^2)
which implies f=k/g^2
since f=8 and g=-2,
f=k/g^2
8=k/(-2)^2
8=k/4
k=32

Now you have k. Thus, f=k/g^2
f=32/4^2 (since g=4)
=32/16
=2

I hope that helps! Good luck! 2
#6
Hey! Let me give you a simple example.
When a is proportional to b,
a=kb, where k is a constant(you can put any random letter)
Then plug in the values you have for a and b and find k. Then use that k value for what you need to calculate.

When a is inversely proportional to b,
then a is proportional to 1/b(as you are getting the inverse of b)
which implies that a=k/b, where k is a constant
Then plug in the values of a and b and find k. Then use the k value for further calculations.

Back to your question...if f is inversely proportional to g^2,
then f is proportional to the inverse of g^2 (i.e. 1/g^2)
which implies f=k/g^2
since f=8 and g=-2,
f=k/g^2
8=k/(-2)^2
8=k/4
k=32

Now you have k. Thus, f=k/g^2
f=32/4^2 (since g=4)
=32/16
=2

I hope that helps! Good luck! Thanks a lot mate!! 👍
0
4 years ago
#7
(Original post by Awais_)
Thanks a lot mate!! 👍
You're welcome! and have a HAPPY NEW YEAR!!! It's 12.08 am here that's why I'm wishing you right now 0
#8
You're welcome! and have a HAPPY NEW YEAR!!! It's 12.08 am here that's why I'm wishing you right now HAPPY NEW YEAR to you too my friend, in England it's 21:11. What country are you in atm? 0
4 years ago
#9
(Original post by Awais_)
HAPPY NEW YEAR to you too my friend, in England it's 21:11. What country are you in atm? Thanks! I'm in Kenya right now 0
#10
Thanks! I'm in Kenya right now Alright, cool!

Best wishes for 2016! 0
4 years ago
#11
(Original post by Awais_)
Alright, cool!

Best wishes for 2016! Thank you!
May you have a wonderful new year! 0
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