Question

${\textbf\red{subject: MATHS}}$



Find the value of x

2/x³ + 5/x =2.85​

Answer 1

Answer:

can you specipy anwser please

Step-by-step explanation:

When multiplying variables in algebra which are the same, you can solve it by adding the exponents. So for example, 2x times x, the answer would be 2x^2. Note that x by itself is actually to the power 1

Answer 2

$\text{Given,}\begin{center} \dfrac{2}{x^3}+\dfrac{5}{x}=2.85 \end{center}\\ \\ \noindent\\ \begin{flushleft}Get the denominators of all the three terms be same. For this, multiply \\ both numerator and denominator of \ \dfrac{5}{x} \ and \ 2.85\ =\ \dfrac{2.85}{1} \ by \ x^2 \ and\\ x^3 \ respectively.\end{flushleft}\\ \\ \dfrac{2}{x^3}+\dfrac{5x^2}{x^3}=\dfrac{2.85x^3}{x^3} \\ \\ \\ \begin{center}\noindent\\ \dfrac{5x^2+2}{x^3}=\dfrac{2.85x^3}{x^3} \end{center}$

$\text{On considering the numerators, we get a cubic polynomial.}\\ \begin{center} 2.85x^3-5x^2-2=0 \end{center}\\ \\ \noindent\\ \begin{flushleft}Let's solve this equation!\end{flushleft}\\ \begin{flushleft}Here the coefficient of \ x^3 \ is a decimal, so first let me remove the decimal \\ part. For this I multiply each term by 20.\end{flushleft}\\ \\ 57x^3-100x^2-40=0$

$\text{Well, solving a cubic polynomial is much tougher, right?!}$

$\text{This polynomial has only one real root and that is estimated to 4 decimal}\\ \text{places as}\ \mathbf{1.9407}. \ \text{The other two roots are}\ \bold{-0.0932\pm 0.5941\iota}.\ \ \left(\iota=\sqrt{-1}\ \!\right)$

$\text{So these are the values of \ x \ estimated.}$