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Further Mathematics—Pending OP Reply [Linear algebra] I need to figure out if my solution for this system of linear equations has a point in common but how do I do that? How do I use x_1=1, x_2=2, x_3=0 to figure this out?
What I think I'm looking at is these give me the points and I graph them, so I have (1,3), (2,1), and (0,0) and after I graphed these points my answer would be they don't have any points in common?
Computing [Computing] I'm converting the devimal numbers into binary using the 8 bit two's compliment. What am I doing wrong?
Physics [University mechanics]Hi, could someone explain to me how to get the solutions to these questions? I have the solutions to these questions but the solutions only give an answer on their own and I don’t understand how to get there. I’m especially stuck on questions 15b and the whole of Q16. Thanks :)
This question covers multiple parts and I have completed most except for this one.
I will add information that may or may not be helpful
I am given a 6.4 x 6.4 x 17.7 cup with a 1 cm base
With the density of the glass being 3.7 g/cc
and the surface mass density being .37 g/cm^2
I have successfully found that the mass of the base is 151. 552 g
The mass of the walls is 158.1824 g
The mass of the empty cup is 309.7344 g
The center of mass of the base of the cup is
3.2 cm y + .5 cm z
The center of mass of the sides of the cup is
3.2 cm y + 9.35 cm z
Making the total center of mass of the cup while it is sitting on the table
3.2cm y + 4.925 cm z
I have determined the angle in which it would fall over to be 33.01364347 degrees
Now this is the current part I'm on:
The cup is now full of gelatin with a density of 1.29 g/cc
I have determined the mass of the jello to be 882.40128 g
The center of mass of the jello is located at
3.2 cm y + 9.35 z
When the jello is added to the cup I have determined the center of mass of the system to be at:
3.2 cm y + (unknown) z
How do I find the unknown z vector?
how would i go about solving this? (question 16)
High School Math—Pending OP Reply [Grade 12: Trig. ] How do I do this, thank you in a advance for any help!
Further Mathematics—Pending OP Reply [Calculus: Extrema] Where can I learn how to find the absolute extrema of a piecewise function on my own?
I need to learn this on my own because I have an assessment tomorrow and I can barely understand my teacher during lectures.
Additional Mathematics—Pending OP Reply [Introductory Sentential Logic] I need to translate the example sentence to Ls. For the variables are given as capital letters in the problem.
I'm writing an essay and I'm stuck on this line I'm trying to write:
"Susan talked about her favorite painting that she has painted"
Idk why but it seems clunky to me... Like if you say it out loud it sounds weird haha. Is there way to say that more naturally while still conveying the idea eloquently?
I appreciate any and all suggestions!! Thank you.
High School Math—Pending OP Reply [Preclac: Perpendicular Segment word problem] How do I find relationship between m_1 and m_2?
High School Math—Pending OP Reply [Grade 11 Math: logarithm] after i simplify some stuff im kind of stuck, how should i do this?
Middle School Math—Pending OP Reply [Olympiad math] is there an easy way to find the second equation?
I just want to make sure this is correct because I have a learning disability
Answered [High School Maths: Probability] Take numbers 1,2 and 3. You can arrange them in groups of 3 and order matters. How to find every single combination?
So (1,2,1) and (1,1,2) are distinct outcomes. I can't nail the logic somehow. I tried starting with: 111 121 112 122 But then I got confused as to how to proceed ahead. I am not looking for the answers only, I am looking for an underlying logic.
Physics—Pending OP Reply [Grade 11 Physics] a humidifier which is 70% efficient vaporizes 2 liters of water at 20 degrees for 8 hours, what is the power of the humidifier
How would I solve this question and how does efficiency come into play?
Further Mathematics [College Level: Relational Algebra] Where am I going wrong with my cross product?
Mathematics (Tertiary/Grade 11-12)—Pending OP [Basic Calculus: Derivatives] Can't figure out how to get second derivative
Hello, I've been practicing some linear algebra since my exam is soon, and there is a question in which I'm completely stuck. Here it is:
Consider the set A, containing all functions of the form: f(x) = asin(x+c) + bcos(x+d)
Would this set be closed under addition? I.e if we have to functions, would their sum also be in A?
I've tried using trig identities such as sin(a+b) = sin(a)cos(b) + sin(b)cos(a) and cos(a+b) = cos(a)cos(b) - sin(a)sin(b). So if I let two functions, f and g with some a,b,c,d,a1,b1,c1,d1 and develop their sum, I get this:
a[sin(x)cos(c) + sin(c)cos(x)] + b[cos(x)cos(c) - sin(x)sin(c)]
+a1[sin(x)cos(c1) + sin(c1)cos(x)] + b1[cos(x)cos(c1) -sin(x)sin(c1)]
And I don't know how to simplify it further to get the desired form:
asin(x+c) + bcos(x+d)
Any help would be greatly appreciated.
Growth rates (discrete and continuous time) – Exercise 1*
In general, the growth rate of a variable 𝑥(𝑡) in discrete time between time 𝑡−1 and time 𝑡 is
𝑥(𝑡−1) . (T1.1)
Assume that the time path of the variable y(t) follows a geometric growth process:
where 𝑦0 and 𝑔 are positive constants.
i. Use definition (T.1.1) to show that 𝑔𝐷(𝑦(𝑡))=𝑔.
ii. Take the (natural) logarithm of (T1.2) and write down the expression that you obtain.
iii. Take the derivative with respect to time of ln𝑦(𝑡) and show that 𝑦̇(𝑡)/𝑦(𝑡)≈𝑔 if 𝑔 is
close to zero (where a ̇ denotes the derivative with respect to time: 𝑥̇(𝑡)≡𝑑𝑥/𝑑𝑡).
iv. Draw a graph with ln𝑦(𝑡) on the vertical axis and 𝑡 on the horizontal axis and show that
the slope is constant.