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How to calculate critical value in hypothesis testing?

You wish to test the following claim ($H_a$) at a significance level of alpha=0.10. $H_o: \mu=70.4$ $H_a: \mu<70.4$ You believe the population is norma...

Published: Sep 06, 2026

general

Elementary product rule for Ito formula

In "Baxter, Rennie" book, there is an explanation of product rule for Ito formula. They apply Ito formula (without any details) to $$\frac{1}{2}((X_t + Y_...

Published: Sep 06, 2026

general

Integrate $ \int \sqrt{\frac{x^3-3}{x^{11}}}\ dx$ [closed]

$$ \int \sqrt{\frac{x^3-3}{x^{11}}}\ dx $$ It seems like substitution could not do it. Is there another way?

Published: Sep 06, 2026

news

Condition of the mean value theorem

The usual formulation of the mean value theorem in a real analysis course is something like this: Let $f\colon [a,b] \to \mathbb{R}$ be continous on $[a,b...

Published: Sep 06, 2026

news

How to find the limit of cos(2x)/x as x approaches zero [duplicate]

Basicly the title. I know it's easy but I can't figure it out. [Edit] Not a duplicate has a 2x instead of x.

Published: Sep 06, 2026

updates

Find, from first principle, the derivative of:

Find, from first principle, the derivative of: $$\log (ax+b)$$ My Attempt: $$f(x)=\log (ax+b)$$ $$f(x+\Delta x)=\log (ax+a\Delta x+b)$$ Now, $$f'(x)=...

Published: Sep 06, 2026

news

Why Two line coincide in the product of reflections

Example. Let $l$ and $m$ be two different lines intersecting at a point $P$. Show that $R_m R_l =R_{p, \theta}$ where $B$ is twice the directed angle $\al...

Published: Sep 06, 2026

news

How do you divide an inequality by another inequality?

The question I'm having trouble with is follows: Suppose you have already proved the proposition that, “If $a$ and $b$ are nonnegative real numbers, ...

Published: Sep 06, 2026

general

The rotation group $SO(3)$ may be mapped to a $2$-sphere by sending a rotation matrix to its first column. How can I describe the fibres of the map?

The rotation group $SO(3)$ may be mapped to a $2$-sphere by sending a rotation matrix to its first column. How can I describe the fibres of the map?

Published: Sep 06, 2026

news

How do you prove a number is prime?

I am a software engineer but try to keep up with maths as I really enjoyed the subject at school. I just saw a great TED talk: Why I fell in love with mon...

Published: Sep 06, 2026