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Help-alevel maths

It says solve 2*5^3x+2=6*7^1-2x
Reply 1
Avatar for mqb2766
mqb2766
21
Original post by starinthenight
It says solve 2*5^3x+2=6*7^1-2x

Assuming its
[br]2∗53x+2=6∗71−2x[br][br]2*5^{3x+2}=6*7^{1-2x}[br]
Try taking logs
Original post by mqb2766
Assuming its
[br]2∗53x+2=6∗71−2x[br][br]2*5^{3x+2}=6*7^{1-2x}[br]
Try taking logs

I have but am still struggling?
Reply 3
Avatar for mqb2766
mqb2766
21
Original post by starinthenight
I have but am still struggling?

Upload what you tried? It should just be the two usual rules
log(ab) = log(a) + log(b)
log(a^b) = b*log(a)
IMG_20210925_082929.jpg
Original post by mqb2766
Upload what you tried? It should just be the two usual rules
log(ab) = log(a) + log(b)
log(a^b) = b*log(a)

Sorry for the blur
For some reason mathway gives a different answer
(edited 2 years ago)
Ngl i think ive given up
Reply 7
Avatar for mqb2766
mqb2766
21
For the left hand side, you have to take log of the whole thing so
log(2*5^(3x+2)) = log(2) + log(5^(3x+2)) = log(2) + (3x+2)log(5)
Similarly for the right hand side and then solve for x.

Note you could have simplified it slightly by dividing by 2 at the start before taking logs
(edited 2 years ago)

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