Mathematics: Post your doubts here!

syed1995

syed1995

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I just hope the examiner doesn't pull his hair after seeing my handwriting.... and deduct marks :\
 
haha101

haha101

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syed1995 said:
naw .. he means

like with

k^2 – 4k < 0
k(k-4)<0
we get two numbers .. k=4 and k=0 .. how does one know which sign to put.. greater then or less then and with which..

k-4<0 .. k<4 ? and k<0 ?
Click to expand...


swhen you simultaneously solve and get one eq of the curve and line . look at the coefficient of the x^2 term if its positive then its a mimimum curve
 
daredevil

daredevil

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syed1995 said:
naw .. he means

like with

k^2 – 4k < 0
k(k-4)<0
we get two numbers .. k=4 and k=0 .. how does one know which sign to put.. greater then or less then and with which..

k-4<0 .. k<4 ? and k<0 ?
Click to expand...
lookie here

umm this is how we did it so u can do it with a graph or a number line its totally up to u.... as the equaiton is <0 so we need the -ve values. now follow me from here: -

_____________0______________4_______ <-- this is my number line (no make fun -.- :p
--------------------------> [more than 0 is this part]
--------------> [more than 4 is this part]
(- and - make +) (+ and - = -) (+ and + make +)

so as we need -ve the area on the number line which is -ve is where we have -ve and +ve bcz + and - make -
so our range will b 0<k<4

PANDA-
 
daredevil

daredevil

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Sarah22 said:
http://papers.xtremepapers.com/CIE/...S Level/Mathematics (9709)/9709_s11_qp_12.pdf
Question- 10 (a)
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Mathematics (9709)/9709_w11_qp_12.pdf
Question- 3(a)
Please.. Thank You
Click to expand...
hey :)
for Q 10a : -
u know from the given data that S6 = 360 because the total angle in a circle is 360
and they are in arithematic progresion which means the first angle is the smallest and they go on increasing so the smallest angle will b the first value i.e. a
largest angle = 4a

use the formula S6 = n(a+l)/2

where a is the first value
S6 is the sum of 6 values
l is the last term

hope u will be able to solve it now becauase after u get a then u just add radii to the arc length
 
Maz

Maz

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I think this will help:
  • If (b^2-4ac) > 0 , the equation will have 2 roots.
  • If (b^2-4ac) < 0 , the equation will have no roots.
  • If (b^2-4ac) = 0 , the equation will have 1 root.
 
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