binomials help ;/ (1 Viewer)

[yellowhighlighterr]

 

[cossine]

View attachment 39294

Question is very easy. Just apply binomial theorem.

Why is nCr used in binomial theorem?

 

[HSCya1234567]

 

[HSCya1234567]

correct me if i mucked up

 

[yellowhighlighterr]

Oooooh my calculator was actin up. soz. but thanks all ^^

 

[yellowhighlighterr]

Question is very easy. Just apply binomial theorem.

Why is nCr used in binomial theorem?

im not sure

 

[yellowhighlighterr]

could i have help with part a please?

 

[HSCya1234567]

View attachment 39296
could i have help with part a please?

its the same sort of reasoning as i was using before, you set up a general expression and chose n = 1 to get the general form for the term in x then you solve for the coefficient = 28 for the first equation. Then you do the same by setting n =2 to get the general form for the term in x^2 and then you have two equations., two unknowns and you can solve simultaneously



let me know if you want working

 

[yellowhighlighterr]

its the same sort of reasoning as i was using before, you set up a general expression and chose n = 1 to get the general form for the term in x then you solve for the coefficient = 28 for the first equation. Then you do the same by setting n =2 to get the general form for the term in x^2 and then you have two equations., two unknowns and you can solve simultaneously



let me know if you want working

yes pls

 

[HSCya1234567]

yes pls

don't know whether this is correct

 

[yellowhighlighterr]

don't know whether this is correct



View attachment 39297

tysm

 

[yellowhighlighterr]

im literally so dumb-


14 a and 15 pls?

 

[tywebb]

Cambridge y11 Ex15C Q14a,15

 

[Drongoski]

correct me if i mucked up

Nicely set out. Your 'x' looks like an 'n'.

Computationally, easier this way.



I recall a young student asked, over 10 years ago, when simplifying a fractional expression, why I had to express the numbers in the numerator and the denominator, via their factors(so I can cancel the common factors, in order to simplify)? Why not just use this marvel of modern living, the calculator, to just multiply out the factors on top and then, divide by the product of the denominators to get the answer! Well, that's how, I believe, lots of students do nowadays.

 

[yellowhighlighterr]

part c

 

[HSCya1234567]

View attachment 39314

part c

i hate to be that person, but what have you tried?

 

[tywebb]

View attachment 39314

part c

Cambridge y11 Ex15D Q7c