IGCSE MATHS Doubts

[Mr.DitD]

Hello everyone!!

I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?! 

[haris94]

y = 10^x

x = 10^y

log x = y

f(-1) x = log x

f^(-1) 1 = log 1 = 0

longer method..

which paper is this from?

this is from O/N 2005

[Ghost Of Highbury]

this is from O/N 2005

check d easier method i posted

[haris94]

if u havent learnt log. try this method

f^-1(1) means, for what value of x in 10^x will u get 1

answer = 0

for e.g f(x) = x+2

          f^-1x = x-2

f(2) = 4

put 4 in f^-1x and u shud get 2

4 -2 = 2

see?

simple.

o i c
yea this is much simpler
havent learnt log
this is the first question of its kind i hv seen though

Thanks a lot

[Dibss]

Hello everyone!!
I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?!  Huh?

if the number is not exact (i.e. it continues after a decimal until the end of your calculator display) you have to give the answer to three significant figures.
write a whole no. only if they specify or if the answer is exact e.g. 517
if the answer is in degrees, give the answer to one decimal place
:]

[ksitna]

Hello everyone!!

I had a confusion about the decimal points. When exactly do we have to put decimal point and we do we have to write whole number?!?! 

u mean like significant figures?
or standard form?

if u meant the answer in the exam
basically write the answers to 2 decimal places

[$H00t!N& $t@r]

if u havent learnt log. try this method

f^-1(1) means, for what value of x in 10^x will u get 1

answer = 0

for e.g f(x) = x+2

          f^-1x = x-2

f(2) = 4

put 4 in f^-1x and u shud get 2

4 -2 = 2

see?

simple.

Can you plz give me some more examples on such kind of ques.

[holtadit]

I remember our teacher giving a horrible explanation about how all rhombuses are squares bla blah


AND


that some parallelograms can be rectangles or soemthing along those lines.

Can someone please please explain this..

[Ghost Of Highbury]

Can you plz give me some more examples on such kind of ques.

check the attached image.

f(x) and f-1(x) is given

u put any values of f-1(x) and calculate u shud get the corresponding value of f(X)

its called one to one function

[Dibss]

Ari, see if these help :]
http://www.algebra.com/algebra/homework/Rectangles/Different-between-parallelogram-rectangle-square-rhombus-and-trapezoid.lesson
http://regentsprep.org/Regents/math/geometry/GP9/LRectangle.htm

[thenewkid™]

gd luck 2 every1. inshallah the exam will be easy.

[Mr.DitD]

So will they EVER cut marks for additional decimals!?!?!
Cuz sometimes u need to use the previous value for getting the next answer and ur answer will be different when you use 3.56 instead of 3.6 or 3!

[Ghost Of Highbury]

I remember our teacher giving a horrible explanation about how all rhombuses are squares bla blah


AND


that some parallelograms can be rectangles or soemthing along those lines.

Can someone please please explain this..

ANy 4 sided figure is called a quadrilateral.

A quadrilateral with opposite sides are parallel and equal in length, and opposite angles equal is called a parallelogram

A parallelogram with 4 right angles and and with congruent diagonals is called a rectangle.

A rhombus is a four-sided shape where all sides have equal length.

Also opposite sides are parallel and opposite angles are equal.

The diagonals of a rhombus bisect each other at right angles.

[Fastal]

ANy 4 sided figure is called a quadrilateral.

A quadrilateral with opposite sides are parallel and equal in length, and opposite angles equal is called a parallelogram

A parallelogram with 4 right angles and and with congruent diagonals is called a rectangle.

A rhombus is a four-sided shape where all sides have equal length.

Also opposite sides are parallel and opposite angles are equal.

The diagonals of a rhombus bisect each other at right angles. (thats wat makes it different from a square)

but a square is a rhombus

[haris94]

question 21 b) please

and can u tell me what is a plane symmetry
and if u hv seen any other questions with plane symmetry in the past papers pls tell me

Thank You