My Math Forum  

Go Back   My Math Forum > High School Math Forum > Algebra

Algebra Pre-Algebra and Basic Algebra Math Forum


Reply
 
LinkBack Thread Tools Display Modes
May 4th, 2014, 02:31 PM   #1
Newbie
 
Joined: May 2014
From: Lancashire England

Posts: 1
Thanks: 0

Unhappy Analytical Methods - Logartithms / Obtaining Expressions

Hello all!

I am new here, and in the UK doing a course on engineering. I have been really struggling with 1 assignment, which i require in for tuesday. A picture of the questions is here (may be 90 degree angle, uploaded funny):

For a) and b) on here I have worked out A) 15.34, and B) 47.925.




Apart from the 2 I answered above, I am totally confused by these
Furinkazen is offline  
 
May 4th, 2014, 06:07 PM   #2
Math Team
 
Joined: Dec 2013
From: Colombia

Posts: 7,398
Thanks: 2477

Math Focus: Mainly analysis and algebra
c) We just take logarithms of both sides, so $\log{y} = \log{kn^w} = \log{k} + w\log{n}$

The rest of that page should be straightforward.

Task 4
a) $R\sin{(wt + a)} = R\left(\sin{wt}\cos{a} + \cos{wt}\sin{a}\right)$. Comparing coefficients of $\sin{wt}$ gives you one equation, the coefficients of $\cos{wt}$ give you a second. You can then solve these simultaneous equations for $R$ and $a$.

b) Period $T = \frac{1}{f}$ and angular velocity $w = \frac{2\pi}{T}$ (you can work these equations out simply by comparing the units).

d) The equation will give an infinite number of solutions because the current is periodic. They want the one where $0 \le t \le 10 \text{ms}$.

Task 5
a) Plug the values in and see what comes out.
b) Acceleration is rate of change of velocity, or how velocity changes with respect to time. Therefore we differentiate the velocity with respect to time. Then, Newton's Second Law $F = ma$ applies. Is the force in the same direction as the velocity, or against it?
c) Put $a = 0$ and solve for $t$.
d) Velocity is the rate of change of position. So we must integrate (with respect to time) the expression for velocity to obtain an expression for the distance travelled.
v8archie is offline  
Reply

  My Math Forum > High School Math Forum > Algebra

Tags
analytical, expressions, logartithms, methods, obtaining



Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
obtaining stationary values kgiboin Calculus 2 March 24th, 2013 05:15 PM
The probability of obtaining 3 and a tail Chikis Advanced Statistics 56 July 30th, 2012 03:43 AM
Obtaining a formula senogles100 Calculus 5 May 1st, 2012 01:25 AM
Analytical methods finfanillo Linear Algebra 0 March 21st, 2012 10:14 PM
Obtaining a formula senogles100 Algebra 3 December 31st, 1969 04:00 PM





Copyright © 2018 My Math Forum. All rights reserved.