Solve the equation $1 + \sqrt{x} = \sqrt{1+x^2} $ graphically on the interval $[-1,5]$. State each answer correct to two decimals.
Based from the graph, the equation $1 + \sqrt{x}$ and $\sqrt{1+x^2}$ is equal when $x \approx 0$ and $x \approx 2.20$
By solving the exact value,
$
\begin{equation}
\begin{aligned}
1 + \sqrt{x} &= \sqrt{1+x^2} \\
\\
1 + 2\sqrt{x} + x &= 1 + x^2 && \text{Square both sides}\\
\\
2\sqrt{x} + x &= x^2 && \text{Subtract } 1\\
\\
2\sqrt{x} &= x^2 - x && \text{Subtract } x \\
\\
4x &= x^4 - 2x^3 + x^2 && \text{Square both sides}\\
\\
x^4 - 2x^3 + x^2 - 4x &= 0 && \text{Subtract } 4x\\
\\
x\left( x^3 - 2x^2 + x - 4 \right) &= 0 && \text{Factor out } x\\
\\
x = 0 \text{ and }x^3 - 2x^2 + x - 4 &= 0 && \text{Zero product property}
\end{aligned}
\end{equation}
$
By using calculator the solutions $x^3 - 2x^2 + x - 4 = 0$ are $x = 2.3146, \quad x = 0.1572+1.305i, \quad $ and $x = -0.1572 - 1.305i$
Thus, the real solution for the equation is...
$x = 0$ and $x = 2.3146$
Thursday, June 9, 2016
College Algebra, Chapter 2, 2.3, Section 2.3, Problem 48
Subscribe to:
Post Comments (Atom)
Why is the fact that the Americans are helping the Russians important?
In the late author Tom Clancy’s first novel, The Hunt for Red October, the assistance rendered to the Russians by the United States is impor...
-
Lionel Wallace is the subject of most of "The Door in the Wall" by H.G. Wells. The narrator, Redmond, tells about Wallace's li...
-
In the late author Tom Clancy’s first novel, The Hunt for Red October, the assistance rendered to the Russians by the United States is impor...
-
The poem contrasts the nighttime, imaginative world of a child with his daytime, prosaic world. In the first stanza, the child, on going to ...
-
Friar Lawrence plays a significant role in Romeo and Juliet's fate and is responsible not only for secretly marrying the two lovers but ...
-
There are a plethora of rules that Jonas and the other citizens must follow. Again, page numbers will vary given the edition of the book tha...
-
Resourceful: Phileas Fogg doesn't let unexpected obstacles deter him. For example, when the railroad tracks all of a sudden end in India...
-
If by logos you mean argument by logic or the use of facts to prove a point, then there are plenty of examples in the book. Take, for instan...
No comments:
Post a Comment