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The domain and range of a quadratic function |
2007-07-17 |
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From Linda:
I have been trying to solve this problem but I'm unable to figure it out. How do I find the domain and range of
y=-(x+1)^2-3? Please explain...thanks!
Answered by Stephen La Rocque and Penny Nom. |
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Sample size |
2007-07-17 |
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From Nurse:
If a population has standard deviation 20, what is =
the
minimum sample size to be 95% confident that the error should be =
accurate to
within 4?
Answered by Harley Weston. |
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A model for a building |
2007-07-17 |
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From Carl:
A model for a building is 50 centimeters long, 38 centimeters wide, and 225 centimeters tall
on model 1 centimeter represents 2.5 meters.
I need to find the volume of the actual building in cubic meters,and the surface area of the building including
ceilings and floors. round to the nearest tenth of a square meter.
Answered by Harley Weston. |
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The height of a triangle |
2007-07-17 |
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From linda:
IF AREA EQUALS 12radical 30 of the triangle find the height B= 3 radical 3
Answered by Penny Nom. |
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Radical 96 plus radical 27 divide by radical 3 |
2007-07-17 |
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From linda:
radical 96 plus radical 27 divide by radical 3
Answered by Penny Nom. |
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Divide a square into seven pieces |
2007-07-17 |
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From suzette:
how can you divide a square into 7 equal sizes and shapes?
Answered by Penny Nom. |
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A normal to a curve |
2007-07-16 |
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From Samantha:
The function f is defined by f:x --> -0.5x^2 + 2x + 2.5
Let N be the normal to the curve at the point where the graph intercepts the y-axis. Show that the equation of N may be written as y = -0.5x + 2.5.
Let g:x--> -0.5x + 2.5
(i) find the solutions of f(x) = g(x)
(ii) hence find the coordinates of the other point of intersection of the normal and the curve
Answered by Penny Nom. |
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The isosceles triangle of largest area with perimeter 12cm |
2007-07-16 |
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From sharul:
find the dimension of isosceles triangle of largest area with perimeter 12cm
Answered by Harley Weston. |
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Trig functions for angles not between 0 and 90 degrees |
2007-07-16 |
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From Tim:
My question: Why is the value of a trigonometric function, the same, for an angle over 90 degrees and its reference angle?
How are the angle and its reference related? Do they both form a triangle that has equal sides?
Answered by Penny Nom. |
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Another trig limit |
2007-07-16 |
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From Richter:
lim (π + x)/[cos(x/2)]
x-->-π
Answered by Harley Weston. |
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A trig limit |
2007-07-16 |
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From Richter:
what is the value of lim [cos (π/x)]/(x-2) as x-->2?
Answered by Harley Weston. |
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Height of a tower from two observations |
2007-07-16 |
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From joyce:
An observer wishes to determine the height of a tower. He takes sight @
the top of the tower from A & B w/c are 5oft. apart @
the elevation on a direct line w/ the tower.
The vertical angle @ point A is 30 degrees & the point B is 40 degrees.
What is the height of the tower?
Find the value of x in angle tangent 40 degrees and 30 degrees?
Show the solution of the value of x?
Answered by Stephen La Rocque. |
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Height of an antenna (angle of elevation) |
2007-07-16 |
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From Fhay:
An antenna stands on the edge of the top of a 52 story building from a point 320 ft. from the base of the building, the angle of elevation to the top of the antenna is 64 degrees in each story is 12 ft. high. Find the height of the antenna
Answered by Stephen La Rocque. |
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Finding the area of a circle from its circumference |
2007-07-16 |
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From Amanda:
what is the area of a circle with a circumference of 3000 metres?
Answered by Stephen La Rocque. |
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The two towers (angles of elevation trigonometry) |
2007-07-14 |
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From joyce:
The angle of elevation of tower B from the top of tower A is 28 degrees
and the angle of elevation of the top of tower A from the base is 46 degrees
Find the height of tower A if tower B is 120 m high?
Answered by Stephen La Rocque. |
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