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x = sec^2 3y differentiate

How do i differentiate x = sec^2 3y?

I dont understand if i'm supposed to be using the chain rule or product rule. I've been looking at answers but i just dont understand it
Reply 1
Original post by TomokoRainMaker
How do i differentiate x = sec^2 3y?

I dont understand if i'm supposed to be using the chain rule or product rule. I've been looking at answers but i just dont understand it

What have you tried?
Reply 2
Original post by Muttley79
What have you tried?

i did
U = 3y du/dx = 3
y = sec^2U dy/dx = ksec^2UtanU

idk if thats even right. thats all i have bc idk what rule to use
Find dx/dy. Then use that to find dy/dx.
(You're on the right track for dx/dy)
Reply 4
Original post by TomokoRainMaker
i did
U = 3y du/dx = 3
y = sec^2U dy/dx = ksec^2UtanU

idk if thats even right. thats all i have bc idk what rule to use


dx/dy = dx/du * du/dy

Can't follow your method.

Which of those can you find?
Reply 5
Original post by Muttley79
dx/dy = dx/du * du/dy

Can't follow your method.

Which of those can you find?

How am i meant to know to put it into the chain rule? Thats what i dont get
Reply 6
Original post by TomokoRainMaker
How am i meant to know to put it into the chain rule? Thats what i dont get


You wrote:

U = 3y [du/dx] that is dU/dy as you have an equation between two variables U and y

y = sec^2U [dy/dx] here you have an equation between y and U, so it'd be dy/dU
(edited 5 months ago)

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