2026 HSC CHAT (2 Viewers)

NotBamboo

Well-Known Member
Joined
Apr 2, 2025
Messages
127
Location
Gender
Male
HSC
2026
@Shavi Masee
got it with the help of AI cus i forget about turning point silly me
View attachment 47383
AND CHECKING WITH DESMOS DRUMROLL PLEASE
View attachment 47384

@cheesynooby
can u teach me how to use the element of symbol for domain and range thanks
if anyone is still confused why i used differentiation i found smthing for u
1745122287354.png
in the working out i replaced f'(x) with 0 for the stationary point (that was the word i was looking for)

@cheesynooby is there a better way to solve it that doesn't include derivatives (for shavi to understand)
 

jane1820

Well-Known Member
Joined
Jul 15, 2024
Messages
1,603
Location
Chase Atlantic’s rarri
Gender
Female
HSC
2026
if anyone is still confused why i used differentiation i found smthing for u
View attachment 47391
in the working out i replaced f'(x) with 0 for the stationary point (that was the word i was looking for)

@cheesynooby is there a better way to solve it that doesn't include derivatives (for shavi to understand)
Why r u over complicating stuff omg 😭
here ill send my own working
 

NotBamboo

Well-Known Member
Joined
Apr 2, 2025
Messages
127
Location
Gender
Male
HSC
2026
appreciate it
yeah, actually doing the inequalities was better than randomly testing and graphing points
also what is this 'sub in any random number from' u couldve phrased it any other way 😭 like 'test... neg number, pos number'

whered u spawn in the desmos graph from
your range; (-infinity, 0.5) does not look right, the graph does not ever touch y=0
i can sub in 0.6 and get still an answer so ur max is wrong too silly
 

jane1820

Well-Known Member
Joined
Jul 15, 2024
Messages
1,603
Location
Chase Atlantic’s rarri
Gender
Female
HSC
2026
appreciate it
yeah, actually doing the inequalities was better than randomly testing and graphing points
also what is this 'sub in any random number from' u couldve phrased it any other way 😭 like 'test... neg number, pos number'

whered u spawn in the desmos graph from
your range; (-infinity, 0.5) does not look right, the graph does not ever touch y=0
i can sub in 0.6 and get still an answer so ur max is wrong too silly
OMG I DIDNT REALISE MY RANGE ABDASDJIASJDAOJDSIA
i meant (-infinity, 0.7) bc according to the graph thats the highest it goes

also dw abt the phrasing lmao as long as it makes sense
 

NotBamboo

Well-Known Member
Joined
Apr 2, 2025
Messages
127
Location
Gender
Male
HSC
2026
OMG I DIDNT REALISE MY RANGE ABDASDJIASJDAOJDSIA
i meant (-infinity, 0.7) bc according to the graph thats the highest it goes

also dw abt the phrasing lmao as long as it makes sense
.7 isnt right either silly
u cant rely on desmos for surds u gotta actually do the math
 

cristal

Well-Known Member
Joined
Oct 16, 2024
Messages
351
Gender
Female
HSC
2027
ok so here's my working
so if you draw up x^2 +2x+3 you can see domain is all real x because it never touches 0 and below due to the square root sign so that's domain

onto the range, so just for the quadratic we can see the minimum value/turning point is -1 (just remembered formula is -b/2a whoops). We use the min value bc the smaller the x value the larger the y value for the function.
Using -1 we sub it into the 1/sqrt of x^2 +2x+3 and our maximum value is 0.7071...
as the quadratic HAS to be greater than 0 (bc you can't do 1/0) and also because when doing square root functions you don't get negative (only outputs positive apparently)
range is : 0 < y </ (less than equal to) 0.7071...

(does this make sense or do I need a diagram?)
 

NotBamboo

Well-Known Member
Joined
Apr 2, 2025
Messages
127
Location
Gender
Male
HSC
2026
ok so here's my working
so if you draw up x^2 +2x+3 you can see domain is all real x because it never touches 0 and below due to the square root sign so that's domain

onto the range, so just for the quadratic we can see the minimum value/turning point is -1 (just remembered formula is -b/2a whoops). We use the min value bc the smaller the x value the larger the y value for the function.
Using -1 we sub it into the 1/sqrt of x^2 +2x+3 and our maximum value is 0.7071...
as the quadratic HAS to be greater than 0 (bc you can't do 1/0) and also because when doing square root functions you don't get negative (only outputs positive apparently)
range is : 0 < y </ (less than equal to) 0.7071...

(does this make sense or do I need a diagram?)
GOOD STUFF KRYSTAL IM PROUD OF U <3
yeah heres my full 12 pages of working out that u did in like 5 sentences
Domain & Range help for my bestie | Bored Of Studies
 

Users Who Are Viewing This Thread (Users: 0, Guests: 2)

Top