# Week 9 – Precalc 11

This week we learned how to model using quadratic functions. I struggled with this question because I had to force myself to look for the opportunity to use this way of solving.

# Blog 5 – Trinomials

This week in pre-calc we learned how to factor using trinomials.

There are a couple steps to figuring this out, but once you have figured it out it is very simple.

1. identify a,b, and c in the trinomial ax2+bx+c.
2. write down all factor pairs of c.
3. identify which factor pair from the previous step sums up to b.
4. Substitute factor pairs into two binomials.

example:

# Blog 6 – quadratic equation

This week in Ms burtons pre calc class we learnt how do solve using the quadratic equation.

To solve this it’s easiest to determine was terms are A,B, and C. Once these variables are determined substitute these variables for the numbers from the equation. Use bedmas to solve for X

This week in precalc I learned that when doing absolute values if a negative number is within braces it really means its a positive absolute value. We know this because it all depends on the numbers distance from 0.

# Week 2 – Geometric Sequences (Infinite Series)

This week we were taught about geometric sequences and infinite and finite series.

Converging = finite

diverging = infinite

finite =  -1<r<1

infinite = r<-1 or r>1

Finite = sum

infinite= no sum

Equations:

$S_\infty = \frac{a}{1-r}$

# Week 1 – Arithmetic Sequence

$S_n=\frac{n}{2}(t_1+t_n)$

My arithmetic Sequence: 5, 10, 15, 20, 25

$t_1=5$ $t_{50}=?$ $S_{50}=?$

d = 5

$t_{50}=5+(50-1)5$ $t_{50}=250$

$S_{50}=\frac{50}{2}(5+50)$ $S_{50}=25(55)$

$S_{50}= 1375$ $t_{50}=250$