×

ABC Formula in Cubic Equation

We know that for quadratic equation $$ax^2+bx+c=0$$ , where $$a$$ is a non zero number,

we can use the ABC Formula to determine the value of x.

Here is how we get the value of x.

$$ax^2+bx+c=0$$

$$x^2+\frac{b}{a}x+\frac{c}{a}=0$$

$$x^2+\frac{b}{a}x=-\frac{c}{a}$$

$$x^2+\frac{b}{a}x+(\frac{b}{2a})^2=-\frac{c}{a}+(\frac{b}{2a})^2$$

$$(x+\frac{b}{2a})^2=-\frac{c}{a}+(\frac{b}{2a})^2$$

$$(x+\frac{b}{2a})^2=-\frac{c}{a}+\frac{b^2}{4a^2}$$

$$(x+\frac{b}{2a})^2=\frac{b^2-4ac}{4a^2}$$

$$x+\frac{b}{2a}=\pm\frac{\sqrt{b^2-4ac}}{2a}$$

$$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$$

Then how about cubic equation $$ax^3+bx^2+cx+d=0$$ ?

Note by Andy Leonardo
1 year, 6 months ago

MarkdownAppears as
*italics* or _italics_ italics
**bold** or __bold__ bold
- bulleted- list
• bulleted
• list
1. numbered2. list
1. numbered
2. list
Note: you must add a full line of space before and after lists for them to show up correctly
paragraph 1paragraph 2

paragraph 1

paragraph 2

[example link](https://brilliant.org)example link
> This is a quote
This is a quote
    # I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
# I indented these lines
# 4 spaces, and now they show
# up as a code block.

print "hello world"
MathAppears as
Remember to wrap math in $$...$$ or $...$ to ensure proper formatting.
2 \times 3 $$2 \times 3$$
2^{34} $$2^{34}$$
a_{i-1} $$a_{i-1}$$
\frac{2}{3} $$\frac{2}{3}$$
\sqrt{2} $$\sqrt{2}$$
\sum_{i=1}^3 $$\sum_{i=1}^3$$
\sin \theta $$\sin \theta$$
\boxed{123} $$\boxed{123}$$

Comments

Sort by:

Top Newest

You will get your answers here

- 1 year, 6 months ago

Log in to reply

Thankyou Sambhrant , it's really helpful.

- 1 year, 6 months ago

Log in to reply

×

Problem Loading...

Note Loading...

Set Loading...