Expressions Definition and 322 Threads

Homework Statement In an organism allele for red eye colour is dominant over allele for white colour. A cross is made between a white eyed male and a red eyed female. In the progeny all males are red eyed and females are white eyed. The reciprocal cross leads to all red eyed progeny. Based on...

Greg Bernhardt submitted a new PF Insights post The 10 Commandments of Index Expressions and Tensor Calculus Continue reading the Original PF Insights Post.

When I use Latex, the expression always comes out on a separate line. How do I keep the expression on the same line?

Homework Statement Hi I am looking at part a). Homework Equations below The Attempt at a Solution I can follow the solution once I agree that ## A^u U_u =0 ##. However I don't understand this. So in terms of the notation ( ) brackets denote the symmetrized summation and the [ ] the...

Given h(x) = tan x, evaluate dh/dx on [pi/4, 1]. Note: d = delta I need one or two hints. I can then try on my own.

Homework Statement Use the power reducing formulas to rewrite the expression that does not contain trigonometric functions of power greater than 1. Given expression: ##4sin^2xcos^2x## 2. Homework Equations Relevant Power-Reducing Formulas: ##sin^2x=\frac{1-cos2x}{2}##...

Until this forum I had never heard of LaTex for writing mathematical expressions. Can anyone help me: A. find out where to download these programs. B. find someone who would be willing to provide guidance on installing and using these programs C. find LaTex and MathJax primers I can print...

Having some trouble determining the most mathematically correct way to express something I understand only numerically and physically. Basically I am modeling radiation within a volume. 1. For each point dV within a volume V there is a scalar value e(dV), which is an amount of radiation emitted...

I have Math Type 6.9 in my computer and everyone of my coworkers has it but there's a problem with mine. Sometimes when I've been working for hours, the math expression I copied from Math Type couldn't get pasted to Microsoft Word (I tried the Save option via Math Type plugin too, and when the...

Homework Statement The apparatus shown may be used to determine the density of an unknown liquid X. The tube has a uniform cross section and the height of the water column is twice that of Liquid X. A and B are the same horizontal level. The pressure difference between points A and C is...

What exactly does it mean to simplify an expression. I understand that an expression becomes more simple when you combine like terms but what other conditions are there? Is x(5x+1) more or less simple than 5x^2 +x? Do square roots need to be moved to the numerator?

Homework Statement Okay, I have two examples that are confusing me. I am not sure where all the numbers that must be excluded from the denominators so that we're not dividing by zero are coming from. a) x2 + 6x +5 / x2 - 25 b) x-7 / x-1 multiplied by x2-1 / 3x-21 Homework Equations None...

Hi there: I am looking for approximate expressions for the two functions: ln(x) and 1/ln(x) . Any help? Thanks in advance.

I'm not sure how to do these problems here. Help me learn them please!

Homework Statement I'm going through the derivation here starting on page 16. This image adds some context: . Generalizing their result to the i'th particle they find the extended distance between two masses being ##\Delta l= \frac{(y_i-y_{i-1})^2}{2a}## Then since the potential energy is...

import java.util.Scanner; public class ShippingCalculator { public static void main (String [] args) { int shipWeightPounds = 10; int shipCostCents = 0; final int FLAT_FEE_CENTS = 75; shipWeightPound = shipCostCost / shipWeightPound; final int CENTS_PER_POUND...

I am attempting to find the solution to the following question. Simplify and state the restrictions on the variables$$\frac{5a^5b^6}{10a^2b^3}\div\frac{2a^4b^2}{20a^3b^5}$$ Not really understanding how to find the restrictions with these set variables.

Homework Statement This excresice is supposed to help you understand the basic operations of sets, later used in probability. I am given the following phrases and have to write them in using mathematics. Given three events A, B and C, which belong to sample space S, calculate the following...

Hi, I got these: $$log(a+b)\approx \frac{b*logb-a*loga}{b-a} + log2 -1$$ $$tan^{-1}(a+b)\approx \frac{b*tan^{-1}2b-a*tan^{-1}2a+\frac{1}{4}*ln\frac{1+4a^2}{1+4b^2}}{b-a}$$ $$sin^{-1}(a+b)\approx \frac{b*sin^{-1}2b-a*sin^{-1}2a+\frac{1}{2}*(\sqrt{1-4b^2}-\sqrt{1-4a^2}}{b-a}$$ And, similarly for...

For the expression: (B and C) or (not B and not C) or (A and (not B) and not C) I get two different answers depending on the order I do the simplification. 1. If I factor C out of the first and third terms I get (B and C) or (A and C) or (not B and not C) 2. If I factor not B out of the...

How do I use the double angle identity in order to derive this expression: cos6(u)?

Problem 1 Simplify/solve: 2*81/2-7*181/2+5*721/2-50 Attempt at solution: a1/2=√a ⇒ 2*√8 - 7*√18 + 5*√72 - 50 = 2√8 - 7√18 + 5√72 - 50 = ? Do not know how to proceed beyond this point. Have experimented with little luck. Problem 2 Simplify/solve: a-1(1+1/a2)-1/2 * (1+a2)1/2 Attempt at...

Homework Statement State an equivalent expression in terms of the related acute angle? (A) cot(-π/4) Homework EquationsThe Attempt at a Solution (A) I made the the unit circle and since its negative I went clockwise and made it into the fourth quadrant. I ended up getting -cotπ/4. However...

I found the above while going through my textbook, where the textbook was trying to explain that the principal value of the product of two complex numbers raised to an exponent is not necessarily equivalent to the product of the two complex number each raised to the same exponent first. Based...

Homework Statement A long air-cored solenoid has two windings wound on top of each other. Each has N turns per metre and resistance R. Deduce expressions for the flux density at the centre of the selenoid when the windings are connected (a) in series, and (b) in parallel, to a battery of EMF E...

Homework Statement teacher gave me the correct solution which said that the result from him was as follows ##\frac{1}{a^2b^6}## Homework Equations original problem was as follows ##\frac{ (\frac{1}{a})^2*b^{-3}}{ ab^3 }## The Attempt at a Solution...

Hello guys, I'm struggling to understand why some expressions are deemed to be extensive(or particularly extensive for that matter) and others are not. As far as I understand, extensive properties are physical quantities whose magnitude is additive for subsystems and this magnitude is...

Homework Statement A single gas molecule of inertia m is trapped in a box and travels back and forth with constant speed v between opposite walls A and B a distance l apart. At each collision with a wall, the molecule reverses direction without changing speed.Write algebraic expressions for the...

Learn how to evaluate an expression with variables using a technique called substitution (or "plugging in"). Watch the next lesson: https://www.khanacademy.o...

We've done a few examples together where we were faced with 1 variable. Why not try one that has 2 variables? Practice this lesson yourself on KhanAcademy.or...

Learn how to evaluate expressions that have two different variables in them by using a technique called substitution (or "plugging in"). Practice this lesson...

In this example we have a formula for converting Celsius temperature to Fahrenheit. Let's substitute the variable with a value (Celsius temp) to get the degr...

We're going to put our order of operations knowledge to work as we evaluate this expression. Exponents, specifically, are our focus here. Watch the next less...

Learn how to write basic algebraic expressions. Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/cc-sixth-grade-m...

Learn how to write simple algebraic expressions. Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/algebra/introdu...

Learn how to write algebraic expressions that involve grouping quantities in parentheses. Practice this lesson yourself on KhanAcademy.org right now: https:/...

"Equivalent algebraic expressions exercise Practice this lesson yourself on KhanAcademy.org right now: https://www.khanacademy.org/math/cc-sixth-grade-math/c...

Euler's constant is defined as ##\gamma = \lim_{n \rightarrow \infty} \left( 1 + {1 \over 2} + {1 \over 3} + \cdots + {1 \over n} - \ln n \right)##. This can be easily represented as an integral: ## \gamma = \int_0^\infty \left( {1 \over 1 - e^{-x}} - {1 \over x} \right) e^{-x} dx \qquad Eq.1...

So if angular momentum L = m r^2 \dot {\theta} and we take the first time derivative \frac {d}{dt} L = 2mr \dot {r} \dot {\theta} + m r^2 \ddot {\theta} the first term looks similar to the Coriolis force 2m( \bf {v} x \bf { \dot {\theta} } ) but I can't figure out why. Of course...

Homework Statement let ##\vec{r}## be a vector from origin to the point (x,y,z) and let ##{\vec{r}\,}'## be a vector from the origin to the point (x',y',z'). Evaluate the following expressions ##1. \triangledown r ## ##2.\triangledown\frac{1}{r}## ##3.\triangledown\cdot r##...

I know that \sqrt{f(x)^2} = |f(x)| However... I've just noticed that integrals of expressions like this are usually assumed to be equal to the integral of f(x) without the absolute value. I'd like to know how that's possible. Is weird for me to consider those expressions; specially because of...

http://imgur.com/RNsBBoO (image) Can someone elaborate as to how he factored this? The textbook provided nothing else about factoring algebraic expressions with fractions than this image.It avoided fractions in factoring like a plague I guess. I understand the 3rd step to put the (x + 1)^(3/4)...

I am not able to express it symbolically I need your assistance. Thanks! A room is $p$ ft. Long and $x$ yards in width; how many yards of carpet two ft. Wide will be required for the floor?

Hi all, Cam google web search accepet regular expressions? Especially, I need to search strings with any number between two words, for example: "vehicle runs at XXX km/h". Thank you

Hi, I have worked the problem but I am not sure that this is the correct answer, Please help. 3(-3) - (5)2^2 ____________ 8- SQRoot(36) +12 I got an answer of 11/14 but When I check on an online calculator to see if it is correct I am getting 5.5 ... 2^2 = TWO SQUARED SQRoot = Square...

Hello! I read about the symmetry of the following product $(x+a+b)(x+b+c)(x+c+a)$ my book says that a, b and c occur symmetrically. Why is that?

Homework Statement The problem comes in second term after 4(2z...) Homework EquationsThe Attempt at a Solution so i got 4 (8z^3) 5k. 32 (z^3) * (20k). After that i left it like that but I supposed to get answer like this 160 z^3 * k I can conjoin constants of z and k variables? Or am I...

Hi, I am struggling to understand the maths in the text shown below. (1) How does: r(t) = Acos(wt)+Bsin(wt) become; sqrt((A^2)+(B^2))cos(wt - arctan(B/A))? (2) He states that we can represent the input as a phasor and in one of three ways but doesn't say which one. (3) He then focus on the...

1/2x-7/x-3 Subtract