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I started with Euler's identity and manipulated it |
2011-11-14 |
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From anonymous:
I started with Euler's identity and manipulated it
e^i*pi=-1
e^-i*pi=(-1)^-1
e^-i*pi=-1
e^-i*i*pi=(-1)^i
e^--pi=(-1)^i
e^pi=(-1)^i
type it in in a calculator and you get e^pi=23.1406926... and
(-1)^i=0.0432139183... What did I do wrong?
Answered by Robert Dawson. |
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Lines tangent to y^2=4x |
2011-11-11 |
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From Reuchen:
Find equations of the lines tangent to y^2=4x and containing (-2,1).
Answered by Penny Nom. |
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The dimensions of a rectangle |
2011-11-11 |
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From Ivan:
The length of a rectangle is 31 centimeters less than five times its width. Its area is 72 sq centimeters. Find the dimensions of the rectangle.
Answered by Penny Nom. |
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A log equation in exponential form |
2011-11-11 |
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From Sarah:
Express the equation in Exponential form
log2 to the 16th power=4
Answered by Penny Nom. |
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The slope of a line |
2011-11-10 |
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From Sara:
Line k lies in the xy-plane.
The x-intercept of line k is -4.
And line k passes through the midpoint of the line segment whose endpoints are (2,9) and (2,0).
What is the slope of line k?
Give the answer as a fraction.
Answered by Penny Nom. |
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1 third plus 5 sixths |
2011-11-10 |
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From Matt:
1 third plus 5 sixths =
Answered by Penny Nom. |
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What was the cost price of the article? |
2011-11-10 |
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From tashana:
By selling an article for $320,the profit was 20% of the cost price.what was the cost price of the article.
Answered by Penny Nom. |
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The perimeter of a quarter circle |
2011-11-10 |
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From sierra:
how do you figure the perimeter of a quarter circle that has a radius of 12
Answered by Penny Nom. |
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A word puzzle |
2011-11-10 |
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From kevin:
ABCD
ABCD
ABCD
ABCD
-------
EBEA
What does each letter stand for?
I've been at it for days and still have nothing.
Thank you,
Kevin
Answered by Robert Dawson. |
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Uses of logarithms |
2011-11-09 |
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From BEA:
what is the use of logarithmic functions in real life or daily life?
Answered by Penny Nom. |
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0.5 acres of land |
2011-11-09 |
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From Kim:
I have .5 acres of land. I want to divide it into 20x20 squares. How many squares will I have?
Answered by Penny Nom. |
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un triangle |
2011-11-07 |
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From Haelita:
La corde élastique a une longueur de 60cm au repos . Quelle est la nouvelle longueur de la corde si on l'écarte de 11 cm en la tirant par son milieu ?
Answered by Claude Tardif. |
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The sum of a series |
2011-11-07 |
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From Rattanjeet:
Find the sum of 1(1/2) + 2(1/4) + 3(1/6) + 4(1/6)(3/4) + 5(1/6)(3/4)2 + 6(1/6)(3/4)3+ ... where 1/6 + (1/6)(3/4) + (1/6)(3/4)2 + ... constitutes a geometric series.
Answered by Penny Nom. |
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The volume of a berm |
2011-11-04 |
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From Roy:
I need to know how many cubic yards are in a berm 100 ft long 8 ft high and 32 ft wide at the bottom? Looking from the end of the berm it would look like a trangle. Thanks for the help.
Answered by Penny Nom. |
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A right angled triangle |
2011-10-31 |
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From bijo:
how can i find the tangent point at a circle with origin as center with radius r and the tangent pass through a given point P? I also want to find out the third point of a right angled triangle given other two points?
Answered by Chris Fisher. |
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