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Solve the equation. (Round your answer to four decimal places.)
e2x − ex − 42 = 0

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Answer:

Explanation:

To solve the equation e^(2x) - e^x - 42 = 0 for x, we can make the substitution y = e^x. Then the equation becomes a quadratic equation in y:

y^2 - y - 42 = 0

We can factor the quadratic equation to get:

(y - 7)(y + 6) = 0

So y = 7 or y = -6. But y = e^x, so we have:

e^x = 7 or e^x = -6

The second equation has no real solutions, since e^x is always positive. So we have:

e^x = 7

Taking the natural logarithm of both sides, we get:

ln(e^x) = ln(7)

x = ln(7)

Rounding to four decimal places, we get:

x ≈ 1.9459

Therefore, the solution to the equation e^(2x) - e^x - 42 = 0 is x ≈ 1.9459.

User Luigi Agosti
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