Math  /  Algebra

QuestionWrite the expression as a single logarithm with coefficient 1 . Assume all variables represent positive real numbers. 5) 29logn4y+87logn(16y2)\frac{2}{9} \log _{n} 4 y+\frac{8}{7} \log _{n}\left(16 y^{2}\right) 5) \qquad A) logn(64y9/10)\log _{n}\left(64 y^{9 / 10}\right) B) logn(439/20y63/40)\log _{n}\left(4^{39 / 20} y^{63 / 40}\right) C) logn(4158/63y158/63)\log _{n}\left(4^{158 / 63} y^{158 / 63}\right) D) logn(64y39/40)\log _{n}\left(64 y^{39 / 40}\right)

Studdy Solution

STEP 1

What is this asking? We need to combine these two separate logarithms with fractional coefficients into a *single* logarithm with a coefficient of **1**. Watch out! Don't forget those logarithm rules!
Also, fractional exponents can be tricky, so let's be extra careful with those calculations.

STEP 2

1. Use the power rule
2. Use the product rule
3. Simplify the expression

STEP 3

Remember the power rule: nlogb(a)=logb(an)n \cdot \log_b(a) = \log_b(a^n).
Let's apply this to our first term.
We have 29logn(4y)\frac{2}{9} \log_n(4y), which becomes logn((4y)29)\log_n((4y)^{\frac{2}{9}}).
See? We moved that fraction up as an exponent!

STEP 4

Now, let's do the same thing to the second term.
We have 87logn(16y2)\frac{8}{7} \log_n(16y^2), which becomes logn((16y2)87)\log_n((16y^2)^{\frac{8}{7}}).
Awesome!

STEP 5

Another important rule: logb(a)+logb(c)=logb(ac)\log_b(a) + \log_b(c) = \log_b(a \cdot c).
So, we can combine our two terms from the previous step: logn((4y)29)+logn((16y2)87)\log_n((4y)^{\frac{2}{9}}) + \log_n((16y^2)^{\frac{8}{7}}) becomes logn((4y)29(16y2)87)\log_n((4y)^{\frac{2}{9}} \cdot (16y^2)^{\frac{8}{7}}).
We're getting closer to a single logarithm!

STEP 6

Let's simplify that expression inside the logarithm.
We have (4y)29(16y2)87(4y)^{\frac{2}{9}} \cdot (16y^2)^{\frac{8}{7}}.
Remember that 1616 is 424^2, so we can rewrite this as (4y)29(42y2)87(4y)^{\frac{2}{9}} \cdot (4^2 y^2)^{\frac{8}{7}}.
Now, using the power of a product rule (ab)n=anbn(ab)^n = a^n b^n, we get 429y294167y1674^{\frac{2}{9}}y^{\frac{2}{9}} \cdot 4^{\frac{16}{7}} y^{\frac{16}{7}}.

STEP 7

Now, group the terms with the same base together: 4294167y29y1674^{\frac{2}{9}} \cdot 4^{\frac{16}{7}} \cdot y^{\frac{2}{9}} \cdot y^{\frac{16}{7}}.
Using the rule aman=am+na^m \cdot a^n = a^{m+n}, we get 429+167y29+1674^{\frac{2}{9} + \frac{16}{7}} \cdot y^{\frac{2}{9} + \frac{16}{7}}.

STEP 8

Let's calculate those exponents! 29+167=2763+16963=1463+14463=15863\frac{2}{9} + \frac{16}{7} = \frac{2 \cdot 7}{63} + \frac{16 \cdot 9}{63} = \frac{14}{63} + \frac{144}{63} = \frac{158}{63}.
So, our expression becomes 415863y158634^{\frac{158}{63}}y^{\frac{158}{63}}.

STEP 9

Putting it all together, we have logn(415863y15863)\log_n(4^{\frac{158}{63}}y^{\frac{158}{63}}).
And that's it!

STEP 10

Our final answer is C) logn(415863y15863)\log_n(4^{\frac{158}{63}}y^{\frac{158}{63}}).

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord