Solve for x e^(1-3x)=3-2x
Problem
Solution
Identify the type of equation. This is a transcendental equation where the variable
x appears both in the exponent and in a linear term, meaning it cannot be solved using standard algebraic methods.Apply the Lambert W function, which is defined as the inverse of
ƒ(w)=w*e^w To use it, we must manipulate the equation into the formƒ(x)*e^ƒ(x)=C Rearrange the equation by multiplying both sides by
e^(3*x) to move the exponential term to the other side.
Multiply both sides by
e^3.5 or adjust the linear term to match the exponent. Letu=3−2*x thenx=(3−u)/2 Substituting this into the exponent3*x−1 gives3*((3−u)/2)−1=(9−3*u−2)/2=(7−3*u)/2 Observe that because the linear part and the exponent have different coefficients for
x (−2 vs−3 , the solution involves a complex argument for the Lambert W function or numerical approximation.Use numerical methods such as Newton's Method to find the roots. Let
ƒ(x)=e^(1−3*x)+2*x−3 Evaluate the function at
x=1 ƒ(1)=e^(−2)+2−3≈0.135−1=−0.865 Evaluate the function at
x=0.5 ƒ(0.5)=e^(−0.5)+1−3≈0.606−2=−1.394 Evaluate the function at
x=1.5 ƒ(1.5)=e^(−3.5)+3−3≈0.03 Refine the root near
x=1.5 using iteration. The value where the curve crosses zero is approximately1.488
Final Answer
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