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visits member for 2 years, 10 months
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Feb
2
comment Functional Equation : $f(x) = f(x + y^2 + f(y))$
ah. i see. i just new to learn this kind of problem, not so familiar with this
Nov
9
comment Find formula for transformation from $R^3$ to equation of line
Can you tell me clearer please :)
Nov
9
comment Find basis for $\ker T$ with $T:P_2 \to P_2: T(p(x)) = p(x) + p(-x)$
Can you tell me clearer please :)
Nov
9
comment find $rank(T)$ when $T: P_2\to P_2:T(p(x)) = p(x+1)$
Can you tell me, why T has that matrix representation please ?
Nov
9
comment find $rank(T)$ when $T: P_2\to P_2:T(p(x)) = p(x+1)$
P2 is set of all polynomial that degree less or equal than 2 :)
Sep
13
comment Modulo equation : $\frac{n^{k+1}-1}{n-1} \equiv a{\pmod p}$
Can you tell me, more, please.
Jun
13
comment $f(1)=-3$ and $ f'(x)\geq7$ how small is $f(5)$?
And. this problem is call "how small" make me think about min/max rather than think $f(5)$ is a fixed number :D
Jun
13
comment $f(1)=-3$ and $ f'(x)\geq7$ how small is $f(5)$?
ah. put your solution together with Steven Stadnicki comment to prove f(x) is a linear equation, can solve my question :D
Jun
13
comment $f(1)=-3$ and $ f'(x)\geq7$ how small is $f(5)$?
@Serkan is $f(x)$ linear, right ? But can we have this conclusion ? (I think this obvious, but maybe there some other function, that after you derive, it will be constant too)
Jun
13
comment Multi variable integral : $\int_0^1 \int_\sqrt{y}^1 \sqrt{x^3+1} \, dx \, dy$
@Marvis region over which you are integrating is below the parabola $y=x^2$ from x=0 to 1 Could you explain more, please.
Jun
8
comment Lagrange's method to find min/max question
Sorry. Can I ask you, when I read on Wiki, constraint is an equation. and when I ask my teacher, my teacher say when constraint is inequality, we use another method.
Jun
8
comment Lagrange's method to find min/max question
can you give me an example, please. My teacher says the thing opposite :( that we can sure that no max for that function (in above example)
Jun
3
comment Sum of two divergence series is always divergence series?
@Marvis Oh. sorry so much :( I always think two examples is same :(
Jun
3
comment Sum of two divergence series is always divergence series?
Take opposite of series and plus together is too special in my opinion.
Jun
3
comment Sum of two divergence series is always divergence series?
@DavidMitra yes. I have thought your example before, but it's too special.
May
28
comment Maple: how to solving composite function
No. I don't think it's just for fun. it's nice. but I don't know your solution compare to first one (above post) will be same performance or not :)
May
28
comment Maple: how to solving composite function
Can you explain a bit at line 3 and 4,please. I know how they work, but I really don't understand why it works right. I'm thinking about your nice solution so much. Thanks :)
May
20
comment Min/Max of $f(x,y) = e^{xy}$ where $x^3+y^3=16$
Oh. It likes x=y=2 case when I use Lagrange Multiplier. But at min case, I don't have any idea how to solve by Lagrange Multiplier
May
20
comment Min/Max of $f(x,y) = e^{xy}$ where $x^3+y^3=16$
@N.I ah, I understand. Because I just view fomular from other post , I don't really know different $$ and $ :D
Mar
16
comment Compute lim from Graph
Can you explain why, please. I afraid that lim is 1,5 because when T= 50, it will be 0