# Posts by Damon

Total # Posts: 30,057

**Math, Precalc**

A bearing by the way is the direction of something from you. For example that lighthouse bears 10 degrees off our starboard bow or 27 degrees magnetic. The direction you point the fishing boat is heading.

**Math, Precalc**

Oh the time = 14.2/2 = 7.1 hours

**AAARRRGGGHHH**

A fishing boat leaves port at 4 KNOTS at a HEADING of 80? for 3 hours, then turns to a HEADING of 0? at 3 KNOTS for 4 hours, and finally changes to a HEADING of 200? at 6 KNOTS for 5 hours. At this point, the boat heads directly back to port at a speed of 2 KNOTS. Find the ...

**pre-calculus**

(3x+9)(x+3)/ [(x-5)(x+2)] in the numerator I used 3x+9 instead of x+3 so that as x goes to infinity the fraction goes to 3x^2 + little stuff /x^2 + little stuff ---> 3

**no equal sign, no parenthese**

I have no idea what is numerator and what is denominator and you can not solve an expression.

**Physics**

U = hor speed = 30 cos 60 = 15 Vi - initial ver speed = 30 sin 60 = 26 get time upward v + Vi - 9.81 t 0 = 26 - 9.81 t at top t = 26/9.81 that is half total time range = 2 * 15 * 26/9.81

**Hey, scroll down**

I just did this

**MATH - PLEASE HELP!!**

L = 2 w - 3 and L w = 65 so L = 65/w 65/w = 2 w - 3 65 = 2 w^2 - 3 w 2 w^2 - 3w - 65 = 0 (w+5))(2w-13) positive w = 13/2 = 6.5 etc

**PE**

Do you really think warm up is not important. It sure is for those of us on Medicare :)

**sorry, no way**

Whoever wrote this problem assumed that the sled would have a velocity component of 11 m/s in the downwind direction due to the wind. However a sled (or a ship} is not an airplane or a balloon. if nothing else is pushing it, the wind in fact might not move it at all. The ice ...

**maths**

6 * 9 = 54 cm 10 mm/cm so 540 mm

**Calculus**

add y to both sides of the top equation. but I would do it by elimination, subtract and x is gone.

**Scientific Notation**

No, number between 1 and ten 15 * 10^7 = 1.5 * 10^8

**Rate of Change -Math**

n = number of trial passes p = total pay for day p = 20 + 5 n

**Trig**

u is in first quadrant tan of angle above x axis is 2/7 v is on -y axis so the angle between them is 90 + tan^-1(2/7)

**science**

A = |f1| B = |f2| answer = | A - B |

**sorry, do not understand notation**

do you mean 4* integral dx/(2x+3) or what?

**Math**

10/100 * 100 = 10%

**Science**

16 each way two 16 ohm resistors in parallel 1/R = 1/16 + 1/16 = 1/8 LOL, 8

**Calculus**

1990 - 1626 = 364 (I see where this is going :) 1.07^364 = 4.9624 *10^10 !!!!!! times 24 = 1.19 * 10^12 their return at 7% is far better 1.19 * 10^12 - 2.52 * 10^7 LOL, forget it. 25.2 billion is not even in the ball game.

**math**

n sold originally at p 32 n/27 sold later at 5 p/8 original rev = n p final rev = (32/27)(5/8) n p so (32/27) (5/8) = 20/27

**no way**

1 kg of this fruit costs 300 dollars?

**math**

maybe you mean sqrt (144 + 6^2) ??? that is sqrt (144+36) = sqrt 180 = sqrt (9* 20) =sqrt (9*4*5) = 3*2 sqrt 5 = 6 sqrt 5 = 13.41640786

**math**

concrete: 0.14 x + 0.06 (150) = 0.11 ( x + 150)

**math**

2^(84/6) = 2^14 = 16384

**algebra connections**

every year multiply by 1.025 so 5250 * 1.025^10

**algebra**

100 * 1.02^5 assuming you mean 2% per hour if it is per minute it would be 100 * 1.02 ^300

**Physics**

say they are d = 1 F = k (4)(-2)/1^2 = -8 k attracting later each has average (4-2)/2 = 1 in other words 10 microc each but now they repel (same charge) F = k (1)(1)/1^2 = k -8/+1 = -8

**PHYSIC**

speed = 100 m/s? H = 150 m ? upward trip, t = half flight time 0 = Vi - 9.81 t t = Vi/9.81 150 = Vi t - (1/2)(9.81) t^2 150 = Vi^2/9.81 - (1/2)(9.81)(Vi^2/9.81^2) 150 = Vi^2 / 4.9 Vi = 27.1 m/s then t = 27.1/9.81 = 2.76 going up plus another 2.76 down ---> 5.53 seconds ...

**Maths**

7*10 + 2*1 + 7/10 + 1/100

**need radii**

120 = speed of bucket * radius of handle/radius of barrel

**PHYSICS**

omega = v/r = 15/.33 radians/second .175 * omega

**Calculus**

e^(0 + pi i) = e^0 (cos pi + i sin pi) = 1 (-1 +0 ) = -1 so e^(i pi ) =-1 or e^(i pi) + 1 =0

**Physics**

3 liters N2 to 9 liters H2 9/3 = 3 NH3

**math**

tan 6 = 27,000 /x

**math**

I guess it stays climbing at 13 deg? v = 82 sin 13 h = 7*60*82 sin 13

**College Alg**

.25 = e^-3.2x so ln .25 = -3.2 x x = -ln .25/3.2

**College Alg**

.76 = e^-1.2 t ln .76 = -1.2 t just like your other problem

**physics**

component of gravity force down slope = m g sin 35 so a = g sin 35 10 = (1/2) a t^2 20 /(g sin 35) = t^2

**Please use one name and type once**

http://www.jiskha.com/display.cgi?id=1478484503

**multiple posting**

Please use one name and post once.

**Calc One**

Obviously travel at m = 6.7/.82, the vertex at the top of this parabola, maximum miles for a pound ofCO2

**Calc One**

Is your formula -.41 m^2 + 6.7 m - 44 ?????? or what if so part a is dC/dm = -.82 m + 6.7 that is zero when m = 6.7/.82 which is part b part c include end points check at m = 10 and m = 90 as well as the parabola vertex at 6.7/.82

**fix typos**

I suspect m represents speed, not miles and that C is miles per pound but what does 44/.7m mean?

**Better link for binomial distribution**

http://www.statisticshowto.com/binomial-distribution-formula/

**Statistics**

http://onlinestatbook.com/2/probability/binomial.html C(18,10) = 18!/[10!(18-10)] P(18) = C(18,10) * .3^10 * .7*8

**math**

x^2 + 20^2 = 25^2 x = 15 (this is a 3,4,5 right triangle)

**zero**

If you shot it at 300 degrees from horizontal you shot it into the ground.

**Math**

ten * ten = 100

**Physics**

Please, these problems are just plug in the formula problems, no thought required. Please look them up in your text or Google.

**Physics**

google centripetal acceleration for example http://formulas.tutorvista.com/physics/centripetal-acceleration-formula.html

**Math**

-40/2 -80/4 100/-5 ....... etc

**Calculus - Falling Body Problem**

hint if h = height d^2h/dt^2 = acceleration = -32 ft/s^2 constant dh/dt = speed up

**phy**

The units of A) are acceleration, m/s^2 , not momentum which is mass * velocity so NO WAY If it reversed direction of velocity without changing sign of momentum then obviously it came back with NEGATIVE MASS ! so NO WAY C) well all right D ) LOL, it was thrown at zero speed ? ...

**Physics**

An object of mass 1.00kg is moving over a horizontal circular path of radius 2.00m, with a speed of 3.00ms^-1. Determine: (a) its centripetal acceleration (b) its kinetic energy (c) its period (d) its angular velocity

**probability**

Draw four trees with branches :) 2 of the 16 are banana with basket 2 of the 16 are AT without horn so 4/16 = 1/4 = .25

**Physics**

F = m a = m v^2/r = 10 so mv^2 = 10 r = 10 Ke = (1/2) mv^2 = 5 Joules

**Algebra**

e^x / (x^3 + 1/x^3) multiply top and bottom by x^3 x^3 e^x / (x^6 + 1)

**physics**

v = Vi + a t 0 = 3 + a t t = -3/a d = Vi t + (1/2) a t^2 15 = 3 t + (1/2) a t^2 15 = 3(-3/a) + (1/2) a 9/a^2 15 = -9/a + 9/2a = -9/2a 30 a = -9 a = -9/30

**sir damon plz help me or steve**

well, maybe V = 50 sin (2pift) and i = I sin (2pift - phi) then di/dt = 2pif I cos (2pift-phi) with your numbers 2 pi f = 200 V = 50 sin 200 t i = 20 sin (200 t-phi) di/dt = 4000cos (200 t - phi) now VL = L di/dt = L*4000 cos(200t-phi) so 4000 L = 30 L = 3/400 Vr = iR =R*20 ...

**Calc**

p = 2w + 2 L L = 50/w so p = 2 w + 2 (50/w) p = 2 ( w+50/w) dp/dw = 0 at min or max = 2 [ 1 - 50/w^2 ] w^2 = 50 w = 5 sqrt 2 then L = 50/[5 sqrt 2 ] = 10 srt 2/2 = 5 sqrt 2 LOL, it is square :)

**algebra**

You are welcome.

**algebra**

1/3 = 2/6 = 4/12 1/2 = 3/6 = 6/12 halfway between 4/12 and 6/12 is 5/12

**Physics**

but, but, it would have been fun :(

**Maths**

compounded three times 5% each time 4630.50 * (1.05)^3 in the second one is it compounded once or twice a year? if once 4 = (1+x)^2 2 = 1+x x = 1.00 so 100% doubles the first year, doubles again the second year.

**Physics**

Ac = v^2/R F = m Ac = m v^2/R but F = mu m g so mu m g = m v^2/R mu = (v^2/R)/g ratio of centripetal acceleration to gravitational acceleration :) by the way on earth g is more like 9.81 m/s^2, not 9.88

**physics**

This is a trick question. (a) Since there is no friction, the potential energy at the TOP (at 5 meters), m g h = 3 * 9.8 * 5 becomes ZERO AT THE BOTTOM if you define ground level as zero potential. Note the potential difference depends only on altitude. The ramp changes ...

**Math**

three plus 63/80 16/80 44/80

**Math**

if far less fun than changing them all to xxx/80 :)

**Chemistry**

1/2 after 10 1/4 after another 10 1/8 after a third 10 so 345/8 In general fraction left = 1/2^n where n is the number of half lives

**Physics**

Fx = 181 cos 20.8 normal force = m g - 181 sin 20.8 friction force =.29(mg-181 sin 20.8) ma= 181cos 20.8-.29(mg-181 sin 20.8) divide by m to get a now you do the second one the same way

**Physics Urgent!**

a = -mu g = -.705*9.8 = -6.91 m/s^2 v = Vi + a t 0 = 28.7 - 6.91 t t = 4.15 seconds to stop d = average speed * 4.15 = 28.7/2 * 4.15 = 59.6 meters he stops in 59.6 meters we stop in 59.6 + .427 * 28.7 meters so we better be .427*28.7 = 12.3 meters behind or we hit him just ...

**Physics**

a = change in v /change in time = (6.7 - 12.1)/4 = -1.35 m/s^2 F = m a = - mu m g so mu = 1.35/9.8 = .138 average speed = (12.1+6.7)/2 = 9.4 9.4*4 = 37.6 meters

**Math**

3 [ .035* 3800 ] = 399

**Math**

2 L + 2 w = 44 so L + w = 22 L w = 120 so L = 120/w 120/w + w = 22 w^2 - 22w + 120 = 0 (w-12)(w-10) = 0 ten by 12 :)

**math**

-4*5 = -20

**huh**

Unless it is a square, there is no unique answer.

**Math**

You are welcome :)

**Math**

3(8/8) + 7 /8 = 24/8+7/8 = 31/8 3 7/8

**still math**

You are welcome.

**still math**

combine like terms 3 apples + 4 grapefruits + 2 apples is 5 apples + 4 grapefruits

**Calculus**

-1*2 + 7*3/4

**math**

100 (3240 -2673) /3240

**Trigg county**

5280 * 2 --------- 500 * 2 10560 ------ 1000 10.560 or 10.56 feet = 1/500 of a mile :)

**Math**

I think you may mean: 12 a - 3 b^2 12*9 - 3 * 4^2 108 - 3 * 16 108 - 48 60

**statistics**

http://davidmlane.com/hyperstat/z_table.html

**Math7 grade**

You are welcome.

**Math7 grade**

15 ft * 2 in/ft = 30 in 18 ft * 2 in/ft = 36 in so area on plan = 30*36 = 1080 in^2 on the real size area = 15*18 = 270 ft^2 well to compare them change in^2 to ft^2 there are 12 in /ft so 144 in^2 per ft^2 so 1080 in^2 *1 ft^2/144 in^2 = 7.5 ft^2 or you could say 30 in = 30/...

**Calculus**

You do not say if the wind is coming FROM NE or going TOWARD NE In navigation, sailing, and flying we usually use the FROM convention and your NE breeze has components taking you 80/sqrt 2 south and 80 /sqrt 2 west However you never know with mathematicians

**phy**

The same before and after of course 1200*10+2000*27

**Chem**

well, you have 3 mol of H2 for every mol of N2 so your reaction is not limited by either so You have the same number of atoms of N2 on left as on right so .823/.885 = .93 of each reacted so .07 of each remains .07 * .885 = .062 Mol of N2 still there and .07 * 2.654 = .186 mol ...

**Calculus**

u = 5 cos 30 v = 5 sin 30 so V = 5 cos 30 i + 5 sin 30 J of course cos 30 = sqrt 3 /2 and sin 30 = 1/2 so V = (5 sqrt 3) /2 i + (5/2) j

**Calculus**

sqrt(36 + 64) = sqrt 100 = 10 so that vector is ten units long. If you divide each component by 10, you will get a vector of length one in that same direction so < -6/10 , -8/10 > or < -3/5 , -4/5 > by the way this is a 3,4,5 right triangle :)

**physics**

(a) m g h = 3 g (5) =15g at top BUT I assume you are choosing it to be ZERO at the bottom (b) (1/2)m v^2 = mgh = 15 g of course (c) v = sqrt (2 g h) v = sqrt(10 g) (c)

**Math**

4^2 /2 - 2^2 + 5 8 - 4 + 5 9

**Calculus**

As far as I know the first one is true, they differ by a constant. yes, true say f = x^2 g = x then F = (1/3) x^3 + C1 G = (1/2) x^2 + C2 integral f g dx = (1/3) x^4 + C forget the constants for now, no need F G = (1/6) x^5 like no way :)

**Calc**

dv/dt = a which is constant so v = c + at c is v when t = 0, v0 so v = v0 + a t dx/dt = v = v0 + a t so x = constant + v0 t + (1/2)at^2 constant is x when t = 0 or s0 x = s0 + v0 t + (1/2)at^2 (but we cheated and took physics so knew that)

**Geography**

g = b+40 b/g =3/7 so b =3g/7 so g = 3g/7 +40 7g/7 = 3g/7 + 40 4 g = 40*7 g = 70 b = 3*70/7 =30

**physics**

F = m a 5890 = (1070+2140) a a = 5890/(1070+2140) then Fjeep = 2140 a

**PLEASE CHECK OPERATIONS WITH FRACTIONS PART 2**

13. Kevin had 3/4 yard of string. He used 1/3 of the string for a school project. How many yards of string did he use for his project? A.5/12*** B.1/3 C.7/12 D.1/4 ============================== 1/3 * 3/4 = 1/4 I do not have time to go through all these but noticed this ...