Day: April 16, 2018

Week 9- Analyzing general form of quadratic equation

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In week 9 of pre-cal 11 We learned how to analyze the general form of quadratic equation along with many things.

With analyzing, I mean you factor the equation if it’s factorable. And apply the knowledge I learned from last unit to find the two or 1 roots, and using logical thinking such as the axis of symmetry must have the same distance on the x axis to both roots and etc to find more information without changing the equation into standard form.

Week 8 – Graphing Quadratic Equations

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In week 8 of pre-cal 11, we learned how to graph quadratic equations with the general form and the standard form.

ax^2+bx+c, is the general form of the equation, with this form the equation we can find limited information comes to graphing; we can determine the direction and the compression ratio of the graph from a, and y-intercept from c.

But we can easily change this equation to standard form by completing the square; y=a(x-p)^2+q  from this form of the equation we can determine the position of the vertex with q being the y-axis(+ going up,- going down), p being the x-axis(- going right, +going left) and the direction of opening and the compression ratio of the graph by looking at a,( the ratio of the graph will be congruent to ax^2=y, a determines the direction of the graph( if negative a, facing down, if postive a opens up).

 

Week7- Discriminants

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During week 7 of pre-cal 11, we learned how to find the discriminant of a general form of a quadratic equation.

In this quadratic formula:

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

The discriminant is the part under the root sign:

b^2 - 4ac

Finding the solution to the discriminant of a quadratic equation will provide you will the type of roots you will get from the aforementioned quadratic equation.

To find the discriminant of a quadratic equation you need to learn the meaning of a,b,c in this case:

ax^2+bx+c, is the general form of the equation, and when you are trying to find the discriminant just put b^2-4ac in, such as:

4x^2+2x+6, the discriminant will be 2^2-4(4×6)=-92

And the range the discriminant is in it will provide you with the number of roots you will get from this quadratic equation; If your answer is a positive number, there are 2 roots, If your answer is a negative number, there are no real roots, If your answer is a 0, there is 1 root.