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I need help with number 5

I need help with number 5-example-1
User Egridasov
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1 Answer

1 vote

Answer:

k = 2

Explanation:

To find a value of k such that the equation log_k(8x - 2x²) = 3 has a single solution, we can use the property of logarithms that states:


\large\boxed{\log_a(b) = c \) \iff \( a^c = b}

So, for log_k(8x - 2x²) = 3, we have:


k^3 = 8x - 2x^2

Rearrange the equation so that is in the form ax² + bx + c = 0:


2x^2-8x+k^3=0

In this case:

  • a = 2
  • b = -8
  • c = k³

For a quadratic equation to have a single solution, the discriminant (b² - 4ac) must be equal to zero. Therefore:


(-8)^2-4(2)(k^3)=0

Solve for k:


64-8k^3=0


8(8-k^3)=0


8-k^3=0


k^3=8


k^3=2^3


k=2

Therefore, the value of k is 2.

User Gary Wisniewski
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