Degrees to Radians

Check it out Mrs Robinson its ya boy Rico Gathers a.k.a. Mr. Beastly21 getting these blogs done for ya.
We bout to get out on a fast break with Degrees and Radians ya digg.

Degrees to Radian= degrees x pie/180

Radian to Degrees= radian x 180/pie

Ex1: Convert 60 degrees to Radians

60 x pie/180= pie/3

Ex2: Convert pie/9 to degrees

pie/9 x 180/pie= 20 Degrees


That was a SLAM DUNK with degrees and radians fa real. 3 more blogs to go im puttin in work tonight

Parabola

Ricky Gatz checking in live from the DOOLEY MANSION
Lets find out what i do with Parabolas

Find an equation with vertex (0,0) and directrix x=6

So you know its gonna be x=___y^2

1.) 0-p=6
-p=6
p=-6

2.) 1/4(-6)= -3/2

Put -3/2 back in the original problem you setup

x=-3/2y^2

There it go yah heard me three blogs down and 4 to go lets get it

Circles

It's ya boy Rico gatz in the building getting his blog game on ya digg. Lemme holla at ya real quick about circles.

Ex: find the center and radius by completing the square


X^2 + y^2 - 6x + 4y - 12= 0

1.) x^2-6x+9+y^2+4y+ =12+9
2.) x^2-6x+9+y^2+4y+4=12+9+4
3.)(x-3)^2 + (y+2)^2= 25

Center:(3,-2)
Radius: 5

Advanced Math

1.)

9-1!

This week in class we learned about SOHCAHTOA!

-This means sin x = opp/hyp, cos x = adj/hyp, and tan x = opp/adj.

-Only used on right triangles

-You can’t use 90 degree

- angle of elevation is like this <

- angle of depression is like this ^

Example 1.) In triangle ABC, angle A = 90 degrees, angle B = 25 degrees, a = 18. Find b and c.

To find b you would plug into your formula for sin because b is opposite of 25 and they give you a, which is the hypotenuse.

So, sin 25 degrees = b/18

You would multiply each side by 18 and get b is about 7.607

To find c you would plug into your formula for cos because c is adjacent of 25 and they give you a, which is the hypotenuse.

So, cos 25 degrees = c/18

You would multiply each side by 18 and get c is about 16.314.

b= 7.607 and c= 16.314

! Sohcahtoa !

The latest lesson that we have learned in class was SOHCAHTOA.

SOHCAHTOA= sin= opp/hyp. cos=adj/hyp. tan=opp/adj.

Steps of SOHCAHTOA:

-Only able to use if a right triangle.

-Can't use it on the 90 degree angle.

-Angle of elevation means looking from bottom to top.

-Angle of depression means looking from top to bottom.

Example of SOHCAHTOA:

The safety instructions for a 25 foot ladder indicate that the ladder should not be inclined at more than 60 degrees from the ground. Suppose a ladder is leaned against a house at this angle. Find a) the distance x from the base of the house to the foot of the ladder and b) the height of the ladder.

To find your height, first set up : sin60 degrees=y/25

Multiply each side by 25 to get: y=25sin60= 21.650

To find the distance x: x=cos60=x/25

Multiply each side by 25 to get: x=25cos60= 12.5

IDENTITIES

Steps to finding identities:

• Algebra
• Pythagorean formulas, if not, convert to sin and cos
• Algebra
• Continue steps 1-3

Pythagorean identities are:

1. Sin ^2 theta + Cos ^2 theta = 1
2. 1 + Tan ^2 theta = Sec ^2 theta
3. 1 + Cot^2 theta = Csc ^2 theta

Reciprocal identities are:

• CscX = 1/SinX
• SecX = 1/CosX
• CotX= 1/TanX

Example... Simplify

Sec x - Sin x Tan x

= 1/ Cos x - Sin x ( Sin x/ Cos x)

= 1/ Cos X - Sin ^2 x/ Cos x = 1- Sin ^2 x/ Cos x

= Cos ^2 x/ Cox x = Cos x

1) Changed Sec to 1/cos. Changed Tan to Sin/Cos

2) Multiplied Sin x by whatever was in the parenthesis

3) Used the pythagorean identity Sin^2 theta+Cos^2 theta=1

4) Reduced