Resolve to me these exercises please?

Mathematics

1 answer:

Dima020 [189]3 years ago

7 0

A)4^(n+3)=8^14
2^(2×(n+3))=2^(3×14)
2^(2n+6)=2^42
2^2n=2^36
n=18

b) (assuming a : is divide)
3^(2n+1)=9^17/3^3
3^(2n+1)=3^(2×16)/3^3
3^(2n+1)=3^29
3^2n=3^28
2n=28
n=14

d) (6^n)^4×36=216^10
6^4n×6^2=6^(3×10)
6^(4n+2)=6^30
6^4n=6^28
4n=28
n=7

e)7^(n^2)÷7=49^24
7^(n^2-1)=7^(2×24)
7^(n^2)=7^49
n^2=49
n=7

g)15^(n+4)÷5^(n+4)=81^6
3^(n+4)×5^(n+4)÷5^(n+4)=3^(4×6)
3^(n+4)=3^24
n=20

h)81^n÷9^n+9^(n+2)÷9=90÷9^6
9^2n÷9^n+9^(n+2)÷9=9*10/9^6
9^n+9^(n+1)=10/9^5
I don't know where to go from here

I)what?

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