Calc HELP

[warm cairn]

completely lost i got -3 as my answer

help please

[tough shore]

If F(x) = f(x) + g(x)

How would F'(x) look like?

[warm cairn]

i have no idea bro

@tough shore ive tried for like

20 min using everything ik

i have headaache pls walk me thru this

this is my new question i tried da prev one

[tough shore]

How would you differentiate F = 4x² - x

At least tell all you know if you want help

[warm cairn]

wouldnt that be 8x - 1

[tough shore]

It would

Now imagine f(x) = x² and g(x) = x

you differentiated both functions

So If G = 4f - g

Then

G = 4f' - g' simple as that

That was my point it's a property of differentiation that you can also differentiate the summands separately if there is a sum of functions

[warm cairn]

i se

[warm cairn]

i got this question wrong so i have this

[warm cairn]

i did this but i got the wrong ans

can u walk me thru the steps n then i can do the rest

[tough shore]

You just need to read the slope off

Slope of f and g at x = 6

[warm cairn]

its dis now

[tough shore]

You can draw a triangle below the line

Explain your work

[warm cairn]

slope is x1 x2 / y1 y2right

ys ontop

[tough shore]

Yes

[hollow yoke]

adonhs

[warm cairn]

g
(3, 5 )
(4 , 4)

f
(4,2)
(2,4)

[tough shore]

think about g

x cannot be 4 twice otherwise you have divided by 0

also what is x and what is y

[warm cairn]

mb first is x second is y

i got -1 for slope of g

and f is -1 also

[tough shore]

ok the number dont make sense

but slope of g = -1 is correct

[warm cairn]

wdym

[tough shore]

i understand now

mb

[warm cairn]

so i have slope of both now what do i do?

[tough shore]

f cannot be -1

it's going up

at x = 6

you gotta pick in points withina small range

between 3 and 8 because the line is there constant

[warm cairn]

i got 1

(6,4)
(5,3)

for this

f slope 1*

[tough shore]

so for f we can take (4,2) and (5,3)

yes that's it

Now do the math

G'(6) = 3f'(6) - g'(6)

f'(6) = 1
g'(6) = -1

[warm cairn]

so it'd be 3(1) * -1

[tough shore]

no

G'(6) = 3(1) - (-1)

[warm cairn]

thats what i meant

G(6) = 3(1) * (-1)

which would be -3

[tough shore]

"3(1) * -1 "

[tough shore]

no

[warm cairn]

oops

[tough shore]

3(1) - (-1) = 3 + 1 = 4

[warm cairn]

Wait im lost

how'd u get that

oh

because ur substracting a negative

im stupid

okay so that would be 4

[tough shore]

ye

[warm cairn]

omg finally i ggot one of these right

im gnna try the rest on my own

ill ask questions if i have any

dis da one imma work on

[tough shore]

yea tryit yourself

just keep in mind

[warm cairn]

ye that one was 0

[tough shore]

go at x = 6 and pick a point where x = 7 and x = 5

[warm cairn]

for things like dis would i get the slope using these points

[tough shore]

so you dont go too far away

[tough shore]

because if you, you end up with different slopes that are but meant at different times

yes that's what i mean

[warm cairn]

okay for this one i got slope = 2 for f and then
slope = -1 for g

then i substittuted 4(2) - -1 and got 9

but its wrong

where did i go wrong

[tough shore]

x=3

it'd be right for x =7 eg

left side you need

[warm cairn]

wait

okay i did it from left i got diff slope

hold

4(-4) - (1)

this gave me -17

also wrong

[tough shore]

..

you need to focus more

[warm cairn]

LMAO

i know bru

math not my favorite subject

[tough shore]

xy name

[warm cairn]

My username Xyna

: -(

[tough shore]

ill show atrick

[warm cairn]

?

[tough shore]

draw a triangle at the two points

also make first sure to identify where you want to find out the slope, here x = 3

then go one left or right here left is better

then for the blue

∆y = 3 and ∆x = 1 and the tangent line goes down so we do a minus

∆y/∆x = -3/1 = -3

the same with the red function

∆y = 1 and ∆x = 1

since tangent goes up we do a +

∆y/∆x = +1/1 = 1

So G'(3) = 4(-3) - (1)

∆y is basically y1 - y2 if you notice

∆x is basically x1 - x2

∆ delta resemble here the triangle basically

and means also Difference

[warm cairn]

ah

okay wait this works so much better

so slope there would be
3 for f and then 1 for g

[tough shore]

no look at f

if the tangent line faces down you need to do a minus

additionally

so -3

is slope of f

that's the only nuance here

but i think it's intuitive

a line going down cant have a positive slope and vice versa

[warm cairn]

so like this?

so i'd get like -2 and +1 for slope

@tough shore

[tough shore]

yes

@warm cairn have you finally gotten it?

[warm cairn]

Yep

ty

[tough shore]

close the thread with .solved then 😄

[tough shore]

.solved