Q. giving your answer correct to 3 significant figures.10. Solve the equationln(1+x2)=1+2lnxgiving your answer correct to 3 significant figures.
Combine logarithms: First, let's use the property of logarithms that says ln(a)−ln(b)=ln(ba) to combine the right side of the equation.So we rewrite the equation as ln(1+x2)=ln(e)+ln(x2).
Simplify equation: Now, since ln(e) is 1, we can simplify the equation to ln(1+x2)=ln(x2)+1.
Set up quadratic equation: Next, we use another property of logarithms that says if ln(a)=ln(b), then a=b. So we set 1+x2 equal to e⋅(x2).This gives us the equation 1+x2=e⋅x2.
Solve for x: Now we need to solve for x. Let's expand e∗x2 to ex2 and move all terms to one side to get a quadratic equation.So we have x2−ex2+1=0.
Substitute e value: This simplifies to (1−e)x2+1=0.
Calculate x: Now, we can subtract 1 from both sides to get (1−e)x2=−1.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1. Since e is approximately 2.718, we substitute that in to get x2=−(1−2.718)1.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1. Since e is approximately 2.718, we substitute that in to get x2=−(1−2.718)1. Calculating the denominator, we get 1−2.718=−1.718.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−1/(1−e). Since e is approximately 2.718, we substitute that in to get x2=−1/(1−2.718). Calculating the denominator, we get 1−2.718=−1.718. Now, we find x2=−1/−1.718 which simplifies to x2=1/1.718.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1. Since e is approximately 2.718, we substitute that in to get x2=−(1−2.718)1. Calculating the denominator, we get 1−2.718=−1.718. Now, we find x2=−−1.7181 which simplifies to x2=1.7181. Taking the square root of both sides to solve for x, we get x20.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1. Since e is approximately 2.718, we substitute that in to get x2=−(1−2.718)1. Calculating the denominator, we get 1−2.718=−1.718. Now, we find x2=−−1.7181 which simplifies to x2=1.7181. Taking the square root of both sides to solve for x, we get x20. Calculating the square root, we find x21.
Identify mistake: Next, we divide both sides by (1−e) to solve for x2. So, x2=−(1−e)1. Since e is approximately 2.718, we substitute that in to get x2=−(1−2.718)1. Calculating the denominator, we get 1−2.718=−1.718. Now, we find x2=−−1.7181 which simplifies to x2=1.7181. Taking the square root of both sides to solve for x, we get x20. Calculating the square root, we find x21. However, we made a mistake. We cannot take the square root of a negative number when we are looking for real solutions. The correct step should have been to recognize that x2 cannot be negative, so there must have been an error in our calculations. Let's go back and check our work.
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