Question

Hey guys l need help on this
x^2+3x+2

So what I'm suppose to be doing is to graph quadratic functions.... So can you please help? (: I would appreciate it (:

Answer 1

what multiplies to make 2 and adds to make 3?

Answer 2

or what are the factors of 2?

Answer 3

first thing you need to do is solve for when y= zero to find x intercepts

Answer 4

you do this by factoring which is why I asked what adds to make 3 and multiplies to make 2

Answer 5

next you need to to find y intercept by setting x= 0 and you mark that on the graph along with the x intercepts

Answer 6

then you work your way towards the y intercept from either side by filling in different values of x do you know what I mean?

Answer 7

But is the Vertex (-1.5, 0.5)?

Answer 8

1.find the x and y intercepts

y = 2 when u substitute 0 on x
(0,2)

x= -2 or x = -1 factorise
(-2,0) and (-1,0)

2.find the turning point (quadratic eqn will have one turning point)

differentiate ur function ,equate to zero and solve for x
f'(x) = 2x +3
f'(x) = 0
2x + 3 = 0
x =-3/2

find y
y = (-3/2)^2 + 3(-3/2)

then u get the coordinates of ur turning point

3.check if ur graph is a concave up or concave down

it is concave up if ur function is increasing (f' > 0) and concave down if ur function is decreasing (f'<0)

now u can plot ur graph using intercepts ,and turning point

hope i was of help

Answer 9

lol bro she or he is not about to differentiate anything just saying this clearly is not from a calculus class or is it?

Answer 10

oh sorry my bad I misinformed you ignore the y-int part but for a quadratic equation should be in the middle of the two x-int if you know how to differentiate this will give you the vertex as well. by finding when f'(x) = 0 and then subbing that x value back into the original equation like bekesto said.

Answer 11

wait can please explain again?