Question

Help-I need to graph sin and cos type 2

y=-2sin(3/4x)

0 | 0
pi/2 | 2
pi | 0
3pi/2| -2
2pi | 0

For some reason I am wrong?

Can someone help me.

Answer 1

is this a calculus quesion

Answer 2

its trig

Answer 3

actually your function is undefined in 0
why do you have f(0)=0?

Answer 4

you will need more than just trig to graph this
does your question actually ask to graph? perhaps you should try graphing it by calculator
to graph this you need advanced techniques by hand

Answer 5

eh is the inside part (-3/4)x or -3/4x it is actually ambiguous

Answer 6

well! i believe if it's 3/4x you can draw it

Answer 7

it's positive.

Answer 8

ah darn i'm sleepy i mean (3/4)x

Answer 9

so now it makes sense that 0 gives 0
but pi/2 how did you get 2?

Answer 10

hmm did my last post not help?

its the period again

Answer 11

the period here is 8pi/3

Answer 12

@dumbcow it did work. I tried msging to tell you Thank you! the thing is i have four more to do different problems, and if i mess up it starts me off at four again. @xapproachesinfinity here is an example of my previous question

Answer 13

ok good ... now it should work for every problem. just plug in the different amplitude and period

here you have
A = -2
B = 3/4 ----> period = 2pi/(3/4) = 8pi/3

0 | 0
period/4 | A
period/2 | 0
(3/4)period | -A
period | 0

Answer 14

follow what @dumbcow said

Answer 15

ok so how did you guys get 8pi/3???

Answer 16

3/4 x=2pi then x=2pi/3/4=8pi/3

Answer 17

the period of sinx is 2pi we use that to find the period sin(3/4 x)

Answer 18

@dumbcow explained to you that if we have y=Bsin(Ax)
the period is 2pi/A

Answer 19

ok it's wrong i did (0,0),(2pi/3,2),(4pi/3,0),(2pi,-2),(8pi/3,0)

Answer 20

@dumbcow

Answer 21

oh its because A = -2 , this means the graph is being reflected

stick to the pattern but make sure to include the neg .... so (-A) = -(-2) = 2

Answer 22

in other words flip the 2 and -2 around, the graph should go down first then up

Answer 23

ok so then (0,0), 2pi/3,-2), (4pi/3,0),(2pi,2),(8pi/3,0)