Recent content by glass.shards

Homework Statement In a neighbourhood, 75% of households speak only English at home, and 5% speak only Spanish at home. Four households are randomly chosen. Given that at least one of the four households speaks only Spanish at home, what is the probability that only one speaks Spanish at...

Homework Statement A fine hair separates one end of two pieces of flat glass to form and air wedge.when light of wavelength 670 nm is incident normally, 25 dark bands are observed (with one at each end).How thick is the hair? Homework Equations destructive interference: 2nt =...

Hey tiny-tim! Since it's 1:30 AM over here, I'm guessing you're in a different timezone. :smile: To fill in the blanks, I'm going to say... When something floats, it displaces its own -mass- of water. When something is submerged, it displaces its own -volume- of water. Thanks everyone for all...

Thanks for the replies! What would happen if aluminum wasn't denser than water? (Well in this case the aluminum wouldn't sink... but for the sake of the argument, let's say it does... by being tied down, etc)

Hi tiny-tim, thanks for your reply! The (sample exam) question is as written above, it is a MC question with no values provided. Would it be safe to assume the volume of aluminum the boat is made of is less than the water displaced by the boat's mass... thus the water level falls when the boat...

Homework Statement An aluminum boat is floating in a swimming pool. A hole opens up in the bottom of the boat, and it sinks to the bottom of the pool. Does the water level rise, fall, or stay the same?Homework Equations (Is the buoyancy equation applicable here?)The Attempt at a Solution...

Homework Statement Mondo Inc. estimates that it can sell 3400 of its premium espresso machine, the Caffeinator, at a price of $900 each, but it will lose 100 sales for each $50 increase in price of the machine. Let p be the price and q be the number of machines sold. (a) Write q as a linear...

Thanks for the reply, Hurkyl! Yes, what I meant was "evenly" divisible in terms of integers. Despite it not being "useful" to consider divisibility for non-integers, I am curious if it is actually valid at all to say that 5i is 'evenly' divisible by 5. Is divisibility defined only for...

For example, is 5i "divisible" by 5? Or does divisibility only apply to integers? On that note, is 5pi divisible by 5? Is 5/6 not divisible by 5? Thanks in advance! =)

Here's what I did: tan2x = -24/7 so to find cosx and sinx, I established that on a graph: y = -24 x = 7 r = 25 OR y = 24 x = -7 r = 25 Thus, cos2x = ±7/25. By breaking down cos2x into (1-2(sinx)^2) and (2(cosx)^2-1) and working out the answers, I got those four values.

Here's what I did: tan2x = -24/7 so to find cosx and sinx, I established that on a graph: y = -24 x = 7 r = 25 OR y = 24 x = -7 r = 25 Thus, cos2x = ±7/25. By breaking down cos2x into (1-2(sinx)^2) and (2(cosx)^2-1) and working out the answers, I got four values, as listed in my previous...

If tan2x=(-24/7), find the exact value(s) of sinx and cosx Working out the answers by hand, I get sinx = ±3/5, ±4/5 cosx = ±3/5, ±4/5 But by actually calculating x and plugging it into sinx and cosx, I get sinx = 3/5, 4/5 cosx = 3/5, -4/5 I'm pretty sure that the latter...

If tan2x=(-24/7), find the exact value(s) of sinx and cosxWorking out the answers by hand, I get sinx = ±3/5, ±4/5 cosx = ±3/5, ±4/5But by actually calculating x and plugging it into sinx and cosx, I get sinx = 3/5, 4/5 cosx = 3/5, -4/5I'm pretty sure that the latter are the answers, but how...

Thank you so much!

oh! I think I've got it: divide both sides by cos2x to get tan2x=1 work out four answers to be π/8, 5π/8, 9π/8, and 13π/8 is this correct? Thanks for everyone's quick replies! :D