Saturday

December 3, 2016
Total # Posts: 28,237

**Math**

2^n

*December 2, 2016*

**Math**

5(.07)(8000)=2800

*December 2, 2016*

**Calculus**

Yes, of course -4-1 = -5 :)

*December 2, 2016*

**Calculus**

where do they hit? 4 x^2 = 45 - x^2 x^2 = 9 x = +/- 3 cylinder height = 45-x^2 - 4 x^2 = 45 - 5 x^2 cylinder thickness = dx cylinder circumference = 2 pi x so V=?[0,3]2 pi x(45-5x^2)dx

*December 2, 2016*

**So what?**

no question is asked.

*December 2, 2016*

**physics**

Vertical problem: at max height (half the trip) 600 = Vi t - .5*9.8 t^2 .5*9.8 t^2 - Vi t + 600 = 0 also v = 0 so 0 = Vi -gt t = Vi/g = Vi/9.8 so .5*9.8(Vi^2/9.8^2) - Vi^2/9.8 +600 = 0 600 = .5*VI^2/9.8 Vi = 108 m/s initial up speed t = rising time = 108/9.8 = 11.1 s total ...

*December 2, 2016*

**Finite Math**

A (1.0465)^6 = 15,000 A = 15,000/1.313516 = 11,419.73

*December 2, 2016*

**physics**

Ke = (1/2)(1260)(14.8^2) Joules go ahead and integrate m a dx if you want but energy is a lot easier.

*December 2, 2016*

**Physics**

total weight = (251+350)(9.81) + rhogas 9.81(4/3) pi (9.5)^3 where rhogas is the mass per unit volume of the gas in the balloon weight must = weight of air displaced = rhoout g (4/3)pi(9.5)^3 rho gas = kg/mol * n = .029 n where n is mols in PV =nRT T = 273 + T that we want rho...

*December 2, 2016*

**Pressure in Physics**

60 *9.81/10 N/m^2 or Pascals if you mean on the floor on earth and 10 is the floor area

*December 2, 2016*

**maths**

2 pi Ro = 44 solve for Ro then Ri = Ro - 2 so inner circumference = 2 pi Ri and Path area = pi(Ro^2-Ri^2)

*December 2, 2016*

**math**

16 = 4*4 12 =4*3 so 4*4*3 is LCM = 48 of each 3 packs HD 4 packs buns

*December 2, 2016*

**Physics**

google Bernoulli constant= v^2/2 + g z + p/rho in your units v in m/s p in Pascals(N/m^2) rho = 1000 kg/m^3 for water g about 9.8 v at bottom = 1.2 m/s v at top = 2 v at bottom =2.4 m/s z at top = z at bottom + .2 meters p/rho bottom =143000/1000 so 2.4^2/2 + 9.8(.2)+ 143 = 1....

*December 2, 2016*

**Math**

B yes C 128(0.5)^3 128*.125 = 16 yes D 128*.5^8 = 128* .00390525 = 0.5 YES !!!!!

*December 1, 2016*

**Math**

Gabby drove t-3 hours she drove 2 hours so t-3 = 2 and Ryan drove 5 hours D = Ryan speed * 5 D = Gabby speed * 2 so 5 R = 2 G but G = R+42 so 5 R = 2(R+42) 3 R = 84 R = 84/3 = 28 HUY - The DIFFERENCE is 42

*December 1, 2016*

**Calculus 1**

v = x^3 dv/dx = 3 x^2 dv/dt = dx/dt * dv/dx dv/dt = 4 * 3(121) cm^3/s

*December 1, 2016*

**math**

1000-850 = 150 interest 150 = 850 (.08) t

*December 1, 2016*

**Pre-Calculus**

satellite position is likely to be x, y , z of t :)

*November 30, 2016*

**science**

1. I disagree with you. People just assumed we were at the center. Partly religious 2. agree 3. agree 4. I agree with you. A and B are obvious. D is the sun and moon working together to produce spring tides when the moon is full and new and neap tides when the moon s half moon...

*November 30, 2016*

**Algebra**

v = dh/dt = 32 -32 t at top, v = 0 t = 1 h = 9+16 = 25 ====================== now with algebra 16 t^2 -32 t =9 - h complete square t^2 -2 t = (-1/16)(h - 9) t^2-2t+1 = (-1/16)(h - 9)+16/16 (t-1)^2 = -(1/16)( h-25) t = 1, h=25 same answer

*November 30, 2016*

**precalculus**

1 x +1 y = 2 1 x +1 y = 3 1 1 2 1 1 3 subtract top one from this 1 1 2 0 0 1 oh my! 0x+0y=1 ?

*November 30, 2016*

**College alegbra**

I assume this does not mean the perimeter but the total length of fencing. I assume x is the length and there are 3 y fences P = 2 x + 3 y x y = 1500 so y = 1500/x then P = 2 x + 4500/x x P = 2 x^2 + 4500 2 x^2 - xP = -4500 x^2 -xP/2 = -2250 x^2 -xP/2 + P^2/16 = -2250 + P^2/16...

*November 30, 2016*

**Calculus**

the function climbs uphill 15 from -3 to +12 in its jaunt of +5 from -1 to +4 that means that somewhere in between there the slope of the function is slope = 15/5 = 3 so at some x = c between x = -1 and x=+4slope = f'(c) = 3 so a)

*November 30, 2016*

**Physics**

(1/2) m v^2 = m g h or use Bernoulli (1/2) rho v^2 + rho g h + P = constant here P = 1 atm on top of the tank and at the outflow so the two ways are the same v = sqrt (2 g h ), just like the water fell amount that comes out per second = Q = Area*v = pi r^2 v = pi*10^-4 v so Q...

*November 30, 2016*

**Physics**

F/m = 2/60

*November 30, 2016*

**physics**

a = F/1 = i + 2 j -2 k v = Vi + a t x = Xi + Vi t + (1/2)a t^2 v at 5 = i+0j+2k + 5i +10j -10k = 6i + 10j - 8k x at 5, well assume start at (0,0,0) x = 0 +(i+0j+2k)5 +(1/2)(i + 2 j -2 k)25 = 5i+0j+10k+(1/2)(25i+50j-50k) =17.5 i +25 j -15 k check my arithmetic !

*November 30, 2016*

**Physics**

yes, both in watts or Joules/second

*November 30, 2016*

**Math**

same as when tan = -1 which is when theta = 90+45 =135 = 3 pi/4 or when theta = 360 - 45 = 315 = 7 pi/4

*November 30, 2016*

**Physics**

m v^2/r = 50 * 64 / 8 = 400 m/s^2

*November 30, 2016*

**Calculus AB**

-(x^4 - 5 x^2 + 6) / (x +3^.5) -(x^2-3)(x^2-2) /(x+3^.5) OH LOOK! -(x-3^.5)(x+3^.5)(x^2-2)/(x+3^.5) = -(x-3^.5)(x^2-2) when x is -3^.5 = -(-2*3^.5)(1) = 2 sqrt 3 Now there is a limit and I am at it without you doing some.

*November 30, 2016*

**Calculus**

is x^(1/5) defined and continuous in that interval? (-1)^(1/5) = -1 etc, seems ok how about arc cos x that looks fine x/(x-3) woukld blow up at x = 3, but we do not go there so it is ok but Oh my, sqrt(-1) is imaginary! and is called i for want of a real number to use. It is a...

*November 30, 2016*

**Integral Calculus**

Height = sin x radius = (3 pi/2 -x) = r so dr=-dx d volume = sin x (2 pi r (-dr)) = 2 pi sin x (3pi/2-x)dx =2 pi(3pi/2) sin x dx - 2pixsin x dx = -3 pi^2 cos x - 2 pi [sinx-xcosx] = [-3 pi^2+2pix]cos x -2 pi sin x at pi - at 0 sin is 0 at both so cos pi = -1 so - [-3 pi^2+2pi^...

*November 30, 2016*

**Algebra (Please Check My Answers)**

4. James attached a diagonal brace across a rectangular frame that measures 6 feet by 8 feet. What is the length of the diagonal brace? ~ 2 feet ~ 10 feet ~ 14 feet ~ 48 feet*** =================== 36+64 = 100 sqrt(100) = 10

*November 30, 2016*

**ss**

I am inclined to think you made the correct guess.

*November 30, 2016*

**Math**

Hmm be sure to put the numbers back in to check. a = 20 and c = 10 13 + 3 = 16

*November 30, 2016*

**Math**

a = 2 c a-7 + c-7 = 16 2 c + c - 14 = 16 3c = 30 c = 10

*November 30, 2016*

**Math**

x+35 + 5x-21 =180

*November 30, 2016*

**CHEM 1301**

H = 8/3 *12.2 = 32.5 12.2 + 32.5 = 44.7

*November 30, 2016*

**cal**

Good :)

*November 30, 2016*

**cal**

g = (x-1)/(2x+4) dg/dx = [(2x+4)-2(x-1)]/(2x+4)^2 at x = -1 dg/dx = m the slope = [(-2+4)-2(-2)]/(2)^2 = 6/4 = 3/2 and g = -2/2 = -1 so y = m x + b -1 = 3/2 (-1) + b b = 1/2 so y = (3/2) x + 1/2 or 2 y = 3 x + 1 check my arithmetic!

*November 30, 2016*

**cal typo ?**

g = x -.5 x + 4 did you mean x^2 maybe? or what?

*November 30, 2016*

**Algebra**

4 a + 5.5 c = 92 a + c = 20 4 a + 5.5 c = 92 4 a + 4 c = 80 ------------------subtract 0 + 1.5 c = 12 c = 8 etc

*November 30, 2016*

**math**

maximize .085 x + .068 y x+y <= 50,000 x>=6,000 x<=27,000 y<=34,650 x+y>=1 phony to fill fields I get $3859 at (27000, 23000) ==================== http://www.wolframalpha.com/widget/widgetPopup.jsp?p=v&id=1e692c6f72587b2cbd3e7be018fd8960&title=Linear%...

*November 30, 2016*

**cal**

You are welcome.

*November 30, 2016*

**cal**

3 x^2 dx + 3 y^2 dy = 3 x dy + 3 y dx (y^2 -x)dy = -(x^2-y)dx dy/dx = - (x^2-y)/(y^2-x)

*November 30, 2016*

**Math**

56 = 2 * 28 = 2*2*14 = 2*2*2*7 can not have more than one 2 2*7 = 14

*November 30, 2016*

**math**

2 by 3/2

*November 30, 2016*

**value**

4/5 = .8

*November 30, 2016*

**Math**

+ C :)

*November 30, 2016*

**Math**

x - 6?xdx/( x^2+1) let z = x^2+1 dz = 2 x dx so x dx = (1/2)dz then x - 6?(1/2)dz/z x - 3 ln z x - 3 ln(x^2+1)

*November 30, 2016*

**Math**

?(x^2-6x+1)/(x^2+1) dx =?(x^2+1)dx/( x^2+1)-6?xdx/( x^2+1) = ?dx - 6?xdx/( x^2+1)

*November 30, 2016*

**Portions and integers**

Zero just gives you an arbitrary point on the number line to measure the other two points from. The fact that it happens to be the melting point of ice is irrelevant to this problem. -89 is colder than -39 -89 is LEFT of -39 on our number line -89 < -39 how much colder is ...

*November 30, 2016*

**Not sure**

skin, hair, nails the only thing listed that is related is the hand.

*November 30, 2016*

**physics -- impossible**

if r is the radius above earth center the speed is totally impossible. I suspect a typo

*November 29, 2016*

**Huh initial height?**

If the velocity is only 3 m/s at the bottom, no way it will go up 10 meters. Typo? Did you leave out an initial height?

*November 29, 2016*

**math**

2 x/5 + 35000 = 3 x/4 35000 = 15x/20 - 8x/20 = 7 x/20 5000 = x/20 x = 100,000

*November 29, 2016*

**genetics - no idea**

not my thing - need biology teacher

*November 29, 2016*

**Physics**

LOL valve straight down is stable (pendulum) valve straight up is unstable (balancing pencil on nose) I = mr^2 = 1.005(.36) (about .36) for angle x in radians, restoring moment is about .005*9.81 x r = .003*9.81 x oh well call g = 10 instead of 9.81 = .03 x .03x = -I alpha = -...

*November 29, 2016*

**Algebra 2**

74-m = m/2 + 11 63 = 3 m/2 m = 63*2/3 = 42 74 - 42 = 32

*November 29, 2016*

**maths**

250 - 80 = 170 girls (170/250)100 = ?

*November 29, 2016*

**2**

You can not row cotton profitably everywhere. You need the right soil and water conditions and preferably a large area of flat land. Rice in particular uses very different soil conditions, like wet. Virginia climate was very good for tobacco as was Ky and Tenn.

*November 29, 2016*

**CHECK! LAST TIME MATH!**

100% - 20% = 80% or .8 100% - 10% = 90%

*November 29, 2016*

**CHECK! LAST TIME MATH!**

call it 150 .8 *150 = 120 so yes .9 *120 = 108 so save about 42 total

*November 29, 2016*

**math**

15 is 1/4 of the way around to 60 min 360/4 = 90

*November 29, 2016*

**Check It, Math**

.06*5000 + .08*(10000-5000) = .14*5000 = 700

*November 29, 2016*

**Math**

5(0/10)+ 10/2=5

*November 29, 2016*

**Interest Finite Math**

huh? amount deposited = A Interest earned in 8 years on that is .05 * 8 * A = 1213 A = 1213/0.40

*November 29, 2016*

**Physics**

a 42*9.81 b 42*9.81 cos 34 c force down slope = 42*9.81 * sin 34 so a = 9.81 sin 34 d 3 = .5 (9.81*sin34) * t^2 t is answer to e v = a t = 9.81 sin 34 *t

*November 29, 2016*

**Linear Algebra**

or http://geomalgorithms.com/a02-_lines.html

*November 29, 2016*

**math**

3.25 * 360 = ?

*November 29, 2016*

**Math**

2 n/3 + 8 = 48

*November 29, 2016*

**Social Studies**

I do not see your map. However a major advantage for the North in the Civil War was that the North had a lot more rail transportation, even before Sherman went through.

*November 29, 2016*

**what about it ?**

y = -2 x -16 ???? you do not say what you want done

*November 29, 2016*

**linear programming**

did with linear programming, no need for simplex

*November 29, 2016*

**The Simplex Method**

164 at (8,12) http://www.wolframalpha.com/widget/widgetPopup.jsp?p=v&id=1e692c6f72587b2cbd3e7be018fd8960&title=Linear%20Programming%20Calculator&theme=blue max 10x+7y x+y<=20 x>=3 x<=8 x+y>=1 phony to fill all the blanks

*November 29, 2016*

**Algebra2**

(8^3)^x = 60 ?? 512^x = 60 x = log60/log512

*November 29, 2016*

**algebra**

looks like a letter V with the bottom on the y axis at -2 and slopes of 1 on the right and -1 on the left

*November 29, 2016*

**social studies**

Oh, sorry !

*November 29, 2016*

**social studies**

Van Buren was never president by the way.

*November 29, 2016*

**Social Studies**

I agree with you.

*November 29, 2016*

**Social Studies**

Well, it did not make slavery legal really in Massachusetts for example, but it said the owner could come get him which pretty much amounts to the same thing.

*November 29, 2016*

**Social Studies**

I guess, sort of.

*November 29, 2016*

**Social studies**

Even after they got here it happened google roger williams

*November 29, 2016*

**College Algebra**

2 ln (x-6) well I think x better be greater than 6

*November 29, 2016*

**precalculus**

(2x-1)/(x^2-1) = a/(x+1) + b/(x-1) 2x-1 = ax-a + bx + b 2 = a+b -1 = -a+b -----------add 1 = 2 b b = 1/2 a = 2-b = 3/2 so (3/2) / (x+1) + (1/2)/(x-1)

*November 29, 2016*

**Math**

(3 days/5 gal) * 60 gal = 36 days

*November 29, 2016*

**Math**

s = 5 R = 4 * 5 = 20 (5+x)2 = 20 + x 10 + 2 x = 20 + x x = 10 years from now 20 + 10 = 30

*November 29, 2016*

**Pre-Calculus**

let's put the center of each at 0,0 to make it easy ellipse x^2/a^2 + y^2/b^2 = 1 we could make a and b the same, but that would be a circle and too easy so lets make a = 2 and b = 1 x^2/4+y^2/1 = 1 then major axis along x = 2a = 4 vertex at -2,0 and + 2,0 (also at 0,1 and...

*November 29, 2016*

**Math**

equality wold be x = 5 inequality would be x < or = 5 which we write x </= 5 <5 means less than

*November 29, 2016*

**Math**

I told you above you can buy 1,2,3,4 or 5 but not 6 any positive whole number less than or equal to 5

*November 29, 2016*

**Math**

yes, but what are you going to use 0.454545.... of a CD for?

*November 29, 2016*

**Math**

11x <= 60 x<=60/11 since fractional CDs are not very useful x <= 5 I can buy 1,2,3,4 or 5 but not 6

*November 29, 2016*

**math volume**

I can not see your pictures but Base area = pi d^2 / 4 = pi in^2 base height = 3 pi in^3 = 9.42 in^3

*November 29, 2016*

**social studies**

The western hemisphere, from Brazil to the USA, experienced a huge INVOLUNTARY TRANSATLANTIC migration from Africa.

*November 29, 2016*

**math**

m minibuses m x number in minis n cars n y = number in cars 10 minibuses means m = 10 10 x in buses 6 cars means n = 6 6 y in cars so 10 x + 6 y = 150 but also 5x + 18 y = 150 now we have a plain old 2 eqn, 2 unknown problem multiply the second equation by 2 and we have: 10 x...

*November 29, 2016*

**Physics**

total mass = 2.5+1.2 = 3.7 kg omega = 2 pi f = 2pi/T = sqrt(2300/3.7) = 24.93 so T = .252 second normal force = m g = 1.2 * 9.81 = 11.77 Newtons max friction force = .56*11.77 = 6.59 when does m a = 6.59 N? 6.59 = 1.2 a a = 5.49 meters/s^2 magnitude of a = A omega^2 = A(24.93...

*November 29, 2016*

**Physics**

inward Ac = v^2/r tangential a = dv/dt 7.04 =sqrt[a^2 + (v^2/r)^2 ] 49.56 = 3.03 + v^4/289 v = a t = 1.74 t v^4 = 9.17 t^4 so 46.53 = 9.17 t^4/289 t^4 = 1466 t = 38.3 seconds Check my arithmetic!!!

*November 29, 2016*

**PHYSICS**

omega^2 R double omega, same R, four times 21.3 4*21.3 =

*November 29, 2016*

**Physics**

see http://www.jiskha.com/display.cgi?id=1480442177

*November 29, 2016*