The product of all solutions of the equation e5(log⁡ex)2+3=x8e^{5(\log_e x)^2 + 3} = x^8, x>0x > 0, is:

Answer: e8/5e^{8/5}

Step-by-step solution

Step 1: Take natural logarithm on both sides

To solve an equation where the variable is in the exponent, we can take the logarithm of both sides. Since the base of the exponential is ee, we use the natural logarithm (base ee). This allows us to bring down the exponent using the logarithm property log⁡b(ac)=clog⁡ba\log_b(a^c) = c \log_b a and log⁡eek=k\log_e e^k = k.

Step 2: Rearrange into a quadratic equation

Let y=log⁡exy = \log_e x. Substituting yy into the equation transforms it into a standard quadratic form ay2+by+c=0ay^2 + by + c = 0. This makes it easier to solve for yy.

Step 3: Solve the quadratic equation for log⁡ex\log_e x

We solve the quadratic equation 5y2−8y+3=05y^2 - 8y + 3 = 0 by factoring. The factors are (5y−3)(5y - 3) and (y−1)(y - 1), which gives us two possible values for yy: 3/53/5 and 11.

Step 4: Solve for xx

Now we substitute back y=log⁡exy = \log_e x and solve for xx. Using the definition of logarithm, if log⁡ba=c\log_b a = c, then a=bca = b^c. This gives us two solutions for xx. Both solutions are positive, satisfying the condition x>0x > 0.

Step 5: Calculate the product of solutions

The problem asks for the product of all solutions. We multiply the two values of xx we found. When multiplying exponential terms with the same base, we add their exponents.

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