Recent content by TheHamburgler1

Actually, this could be a Geometric distribution problem right? In that case we would sum x from 5 to 25 of (.1)(.9)^(x-1). This gives 0.5843102

Would we not express each of those via Bin(n,.1) where x=1? If not, how would we express one of them? Thanks

Homework Statement 10% of engines manufactured on an assembly line are defective. If engines are randomly selected one at a time and tested, what is the probability that the first defective engine will be found between the 5th trial and the 25th trial, inclusive? Homework Equations...

Of course, silly me. So I get (e^(-x))((1+e^-x)^-2) Can this be simplified? -Cheers

Homework Statement Find the derivative of (1+e^-x)^-1 Homework Equations The Attempt at a Solution I can't seem to get anywhere with this. Should I be looking for a property of something like the cosh function to apply to this? Thanks

So what you're saying is that I have to show that A is a subset of AUB. This is done by definition that AUB=A+B therefore A is a subset of AUB and it follows (as you said) that P(A) is less than or equal to P(AUB). Correct? What would I do to prove the intersection is less than A? cheers

Homework Statement Prove the following: P(A∩B) ≤ P(A) ≤ P(AUB) Homework Equations The Attempt at a Solution I first attempt to show that P(A) is a subset of P(AUB) which therefore means it is ≤ P(AUB): P(AUB)=P(A)+P(B)-P(A∩B), thus P(A) is a subset of P(AUB)...I think that...

If I am supposed to find the derivative of the equation sin^2(x) the derivative is 2sinxcosx, by the double angle formula can I say that the derivative is therefore sin2x or can I not do this because I am simply finding the derivative.

Homework Statement A person stands 3.6m in front of a wall that is covered floor to ceiling with a plane mirror. His eyes are 1.8m above the floor. He holds a flashlight between his feet and manages to point it at the mirror. At what angel of incidence must the light strike the mirror so...

I got the total resistance to be 8. The total current to be 1.5 because 12/8=1.5, now how do I get the voltage drops?

I got the total resistance and it's 8. How do I calculate the current through each resistor not the total current.

Homework Statement A schematic diagram incorporates a 12V battery in series with a 3.0 ohm resistor. The current then flows through 12 ohm and 4.0 ohm resistors in parallel with each other. a) calculate the current through and voltage across each resistor. 3.0ohm 4.0 ohm 12ohm 24ohm 4.8 ohm...

Right? Wrong?

F2r+-wr=F2(2.1)+-710(4)=280/2.1=1352.38

I got the answer to be 1352.38N