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Solve the equation 10^((x+1)(3x+4))-2*...

Solve the equation
`10^((x+1)(3x+4))-2*10^((x+1)(x+2))=10^(1-x-x^(2)).`

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To solve the equation \[ 10^{(x+1)(3x+4)} - 2 \cdot 10^{(x+1)(x+2)} = 10^{(1-x-x^2)}, \] we will follow these steps: ### Step 1: Simplify the Exponents First, we simplify the exponents in the equation. We can expand the terms in the exponents: \[ (x+1)(3x+4) = 3x^2 + 7x + 4, \] \[ (x+1)(x+2) = x^2 + 3x + 2. \] Thus, our equation becomes: \[ 10^{3x^2 + 7x + 4} - 2 \cdot 10^{x^2 + 3x + 2} = 10^{1 - x - x^2}. \] ### Step 2: Rewrite the Equation We can rewrite the equation as: \[ 10^{3x^2 + 7x + 4} - 2 \cdot 10^{x^2 + 3x + 2} = 10^{1 - x - x^2}. \] ### Step 3: Multiply by \(10^{-(x^2 + 3x + 2)}\) To simplify further, we can multiply both sides by \(10^{-(x^2 + 3x + 2)}\): \[ 10^{(3x^2 + 7x + 4) - (x^2 + 3x + 2)} - 2 = 10^{(1 - x - x^2) - (x^2 + 3x + 2)}. \] This simplifies to: \[ 10^{2x^2 + 4x + 2} - 2 = 10^{-2x - x^2 - 1}. \] ### Step 4: Set \(y = 10^{x^2 + 2x}\) Let \(y = 10^{x^2 + 2x}\). Therefore, we can rewrite the equation as: \[ y^2 - 2 = \frac{10^{-1}}{y}. \] Multiplying both sides by \(y\) gives: \[ y^3 - 2y + 1 = 0. \] ### Step 5: Solve the Cubic Equation Now we need to solve the cubic equation \(y^3 - 2y + 1 = 0\). We can use the Rational Root Theorem or synthetic division to find possible rational roots. Testing \(y = 1\): \[ 1^3 - 2 \cdot 1 + 1 = 0. \] So, \(y = 1\) is a root. We can factor the cubic equation as: \[ (y - 1)(y^2 + y - 1) = 0. \] ### Step 6: Solve the Quadratic Equation Now we solve the quadratic equation \(y^2 + y - 1 = 0\) using the quadratic formula: \[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{-1 \pm \sqrt{1 + 4}}{2} = \frac{-1 \pm \sqrt{5}}{2}. \] ### Step 7: Find Positive Values of \(y\) The possible values for \(y\) are: 1. \(y = 1\) 2. \(y = \frac{-1 + \sqrt{5}}{2}\) (positive) 3. \(y = \frac{-1 - \sqrt{5}}{2}\) (negative, discard) ### Step 8: Back Substitute for \(x\) Now we back substitute for \(x\): 1. For \(y = 1\): \[ 10^{x^2 + 2x} = 1 \implies x^2 + 2x = 0 \implies x(x + 2) = 0 \implies x = 0 \text{ or } x = -2. \] 2. For \(y = \frac{-1 + \sqrt{5}}{2}\): \[ 10^{x^2 + 2x} = \frac{-1 + \sqrt{5}}{2} \implies x^2 + 2x = \log_{10}\left(\frac{-1 + \sqrt{5}}{2}\right). \] ### Step 9: Solve for \(x\) For \(x^2 + 2x - \log_{10}\left(\frac{-1 + \sqrt{5}}{2}\right) = 0\), we use the quadratic formula again: \[ x = \frac{-2 \pm \sqrt{4 + 4\log_{10}\left(\frac{-1 + \sqrt{5}}{2}\right)}}{2} = -1 \pm \sqrt{1 + \log_{10}\left(\frac{-1 + \sqrt{5}}{2}\right)}. \] ### Final Solutions Thus, the solutions to the original equation are: \[ x = 0, \quad x = -2, \quad x = -1 \pm \sqrt{1 + \log_{10}\left(\frac{-1 + \sqrt{5}}{2}\right)}. \]
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