Search our library of MAT questions

Top answers

MAT

All levels

Deduce a formula (in terms of n) for the following sum: sum (2^i * i) where 1<=i<=n, n,i: natural numbers ( one can write this sum as: 12^1+ 22^2+ .. +n*2^n)

Let S = sum i* 2ⁱ (i=1,2..n) We multiply this by 2 and we obtain:2S = sum (i2ⁱ⁺¹ ) = sum [(i+1-1) * 2ⁱ⁺¹ ]= sum[ (i+1)2ⁱ⁺¹ ] - sum 2^i+...

Answered by Alexandru S. • MAT tutor

1834 Views

What is the square root of the imaginary number i?
Let's suppose that (0+1i)^0.5= x+iy, where x and y are both real numbers. This is the most general form of a complex number. Now let's square both sides. This gives 0+1i = x²
GD
Answered by George D. • MAT tutor
3301 Views
If a_(n+1) = a_(n) / a_(n-1), find a_2017

We are given; a₁ = 2, a₂ = 6 a_n+1 = a_n / a_n-1 And we want to find a₂₀₁₇. The question is hard because if we tried simply applying t...
TL
Answered by Théodore L. • MAT tutor
2171 Views
How do you solve hard integration questions using information you know
lets try a few integrations. what is integral of dx/(1+x)? You can see that it is in the form of f'(x)/f(x) so it is ln[f(x)] right? now what about integral of (e^x/(1+e^x))dx that is also in the form of ...
DA
Answered by Desmond A. • MAT tutor
1535 Views
How would I go about graph sketching?
You want to look at turning points, intersections and when the gradient is possitive or negative. It is also important to demonstrate what is going on with graphs when they are tending towards 0 (especial...
SG
Answered by Simon G. • MAT tutor
1507 Views
1
2
3
4
5
6

Popular Requests

Maths tutor Chemistry tutor Physics tutor Biology tutor English tutor GCSE tutors A level tutors IB tutors Physics & Maths tutors Chemistry & Maths tutors GCSE Maths tutors

Terms & Conditions|Privacy Policy

CLICK CEOP
Internet Safety

Payment Security

Cyber
Essentials

Cookie Preferences

Search over 10,000 free study notes

Top answers

Deduce a formula (in terms of n) for the following sum: sum (2^i * i) where 1<=i<=n, n,i: natural numbers ( one can write this sum as: 12^1+ 22^2+ .. +n*2^n)

What is the square root of the imaginary number i?

If a_(n+1) = a_(n) / a_(n-1), find a_2017

How do you solve hard integration questions using information you know

How would I go about graph sketching?

We're here to help

Company Information

Popular Requests

© MyTutorWeb Ltd 2013–2025

CLICK CEOP

Search over 10,000 free study notes

Top answers

Deduce a formula (in terms of n) for the following sum: sum (2^i * i) where 1<=i<=n, n,i: natural numbers ( one can write this sum as: 1*2^1+ 2*2^2+ .. +n*2^n)

What is the square root of the imaginary number i?

If a_(n+1) = a_(n) / a_(n-1), find a_2017

How do you solve hard integration questions using information you know

How would I go about graph sketching?

We're here to help

Company Information

Popular Requests

© MyTutorWeb Ltd 2013–2025

CLICK CEOP

Deduce a formula (in terms of n) for the following sum: sum (2^i * i) where 1<=i<=n, n,i: natural numbers ( one can write this sum as: 12^1+ 22^2+ .. +n*2^n)