Math Central - mathcentral.uregina.ca
Quandaries & Queries
Q & Q
. .
topic card  



list of
. .
start over

28 items are filed under this topic.
Solve sinX=0.703X for X 2018-03-13
Answered by Penny Nom.
2^x= -2x - 11 2016-11-27
From Kathy:
I don't know how to start this problem:
2^x= -2x - 11

Answered by Penny Nom.
The height of a parabolic arc 2015-12-30
From Tom:
Is there an algebraic means to determine the highest point of a parabolic arc if the base and perimeter are known?
Answered by Penny Nom.
The positive root of sin(x) = x^2 2015-12-13
From Kemboi:
Find the positive root of the equation sin(x) = x^2
Answered by Penny Nom.
x - 2 Sin[x] = 0 2014-05-08
From chanmy:
please help me to sole this equation x - 2 Sin[x] = 0,thank you
Answered by Penny Nom.
n log n = 36 * 10 ^ 12 2013-11-12
From shihab:
How to find value of n in this equation :

n log n = 36 * 10 ^ 12

Answered by Penny Nom.
Sinx=logx+x^2 2012-11-28
From yasmin:
Answered by Harley Weston.
Using Newton's Method to find a root 2012-04-09
From Nancy:
Use Newton's method to find the real root function, accurate to five decimal places

f(x) = x^5+2x^2+3

Answered by Penny Nom.
A logarithmic equation 2010-09-08
From Rohit:
x^2 + k*ln(x) - c - k = 0

Where k and c are constants.

Answered by Penny Nom.
Arc length and Chord length 2010-03-13
From Darryl:
Is there a formula to determine the chord length of an arc knowing only the arc length and the arc depth (sagitta)? I know you can't find the radius with only these two inputs, but can you find the chord length?
Answered by Harley Weston.
Cooling 2010-03-07
From Lori:
If a house is always at 20 degrees celsius. Water (tea) boils at 100 degrees celsius. 5 minutes later the tea was 70 degrees celsius. Use an equation to predict the temperature after 20 minutes.
Answered by Tyler Wood.
541.39(1 + i)^15 = 784.09 2009-10-14
From Fitore:
Hi, I noticed that this question was already posted up, however I was hoping I could solve it without having to use logs. Can you please help me? The equation is: 541.39(1 + i)^15 = 784.09
Answered by Penny Nom.
Find the central angle 2009-08-18
From Larissa:
In a circle, the length of a chord AB is 4 cm and the length of the arc AB is 5 cm. Find the central angle theta, in radians, correct to four decimal places. Then give the answer to the nearest degree. I think I'm supposed to use Newton's method, but am not sure how to start with this problem.
Answered by Harley Weston.
What is so important about quadratics? 2008-11-29
From zoe:
what is so important about quadratics?
Answered by Harley Weston.
Estimate the cube root of 270 2008-03-11
From Tom:
(a) By plotting suitable graphs, estimate to one decimal place the cube root of 270.
(b) With reference to your answer to part (a), use 8 iterations of a Bisection Search to refine your estimate. Use the nearest whole numbers either side of your estimate from part (a) as starting values.
(c) Using either of your starting values from part (b) as first guess, use the Newton-Raphson method to find the true value of the root (to 6 decimal places). Repeat using the other starting value from part (b) and compare the two results.

Answered by Harley Weston.
How would one find the radius? 2007-12-29
From Ned:
Given an arc with length of 192 inches (don't know chord length), and arc height of 6 inches, how would one find the radius?
Answered by Stephen La Rocque and Harley Weston.
Solve sin(x)=x^2-x 2007-12-11
From ming:
is there anyway you can solve
sin(x)=x^2-x without a calculator?

Answered by Stephen La Rocque.
0 = (1/t) - [ln(1+r) ln(t)] 2007-10-18
From Brandi:
Objective: solve for t, where r = 0.05

0 = (1/t) - [ln(1+r) ln(t)]

Answered by Penny Nom.
Principia Mathematica 2007-04-12
From victoria:
i need help making a poster on emilie du chatelet a great mathematician can you describe the newton principia because i know that she worked on it thanks, victoria
Answered by Stephen La Rocque and Penny Nom.
x^x = 2x 2007-02-22
From ramsay:
This has been bugging me for ages. How do find both real solutions to x^x = 2x? Obviously I have x=2, and there's another at about 0.35, but I can't work it out properly. Any help?
Answered by Penny Nom.
Newton meters and ft-lbs 2006-11-04
From Michael:
What is the correlation between Newton meters and ft-lbs of torque? If an engine has 100ft-lbs of torque,what would that equate to in Newton meters?
Answered by Stephen La Rocque.
Computing gravity 2006-09-27
From Patricia:
What is the gravity of planet z in inch/hr squared if the weight of an element with mass of 45000 oz on planet z is 2N?
Answered by Stephen La Rocque.
The area of a sector and a triangle 2006-06-23
From Howard:
I thought of the following problem which is similar but much simpler than the tethered goat problem: What is the angle(it is more illustrative in degrees)of arc of a unit circle so that the area between the chord it subtends and the arc length is equal to the area of the triangle with opposite side the subtended chord.
Answered by Stephen La Rocque and Penny Nom.
The interior angles of a right triangle 2006-05-20
From Greg:
I am wondering if there is a way to figure out the interior angles of a right triangle if we know ONLY the side lengths, and the trick is, we CANNOT use arctangent!
Answered by Leeanne Boehm and Penny Nom.
Square roots and inequalities 2004-10-25
From Waheed:
Q1. What is the simplest way of finding a square root of any number using just a pen and paper? (I am asking this question because I browsed a few sites a didn't find any method that is simpler than the one I use. so I am just curious.)

Q2. Is it possible that you take an equation and turn it into an inequality by performing same mathematical operations on both sides?

Answered by Claude Tardif and Penny Nom.
Newton's binomial theorem 2003-08-30
From William:
According to page 126 of Murtha & Willard's "Statistics and Calculus" (Prentice-Hall, 1973), Newton's binomial theorem can proved inductively. I suppose that was his method, which I would like to see.
Answered by Penny Nom.
Rolling 5 sevens before rolling a six or an eight 2002-01-20
From Tony:
When rolling 2 dice, what is the probability of rolling 5 sevens before rolling a six or an eight?
Answered by Andrei Volodin and Penny Nom.
Solving x - sin(x) = constant 2000-12-29
From Keith Roble:
If x is in radians, how do you solve for x, where: x-sin(x) = constant?
Answered by Harley Weston.



Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.



Home Resource Room Home Resource Room Quandaries and Queries Mathematics with a Human Face About Math Central Problem of the Month Math Beyond School Outreach Activities Teacher's Bulletin Board Canadian Mathematical Society University of Regina PIMS