SC mathematics Marathon (1 Viewer)

[dionb2014]

Yeah just like the science Marathon Guys and girls. Just show your working and whatever.
What is the line perpendicular to -
Y=2x+7

 

[reality3435]

not trying to burst your bubble but isn't maths a little hard to ask over the net?

anyhow

m1 = 2 (given)
m1 * m2 = -1 (product of gradients of perpendicular lines is -1)
2m2=-1
m2=-1/2

:. the gradient of the line perpendicular to y = 2x+ 7 is -1/2

For what values of a is Y=ax a tangent to y= (x^2) - x -2 (sorry i'm not sure if this is school cert standard)?

 

[dionb2014]

You would think so but I have seen extension 2 math marathons with hundreds of Posts. Probs thousands.

 

[twinklegal19]

For what values of a is Y=ax a tangent to y= (x^2) - x -2 (sorry i'm not sure if this is school cert standard)?

Doubt it, have you seen the past school cert maths papers? haha

 

[RealiseNothing]

x=-4x+1

Find x

 

[dionb2014]

It will obviously be better to go into the exam with experience in harder questions than just hard enough. What band are you aiming for.
Q)

 

[zombies]

x=-4x+1

Find x

x = -4x + 1
5x = 1
x = 1/5

It will obviously be better to go into the exam with experience in harder questions than just hard enough. What band are you aiming for.
Q)

They're not gonna ask us anything to do with logarithms.. heck, I don't even remember how to do them lol.

 

[dionb2014]

x=-4x+1
5x = 1
x = 1/5

 

[bleakarcher]

It will obviously be better to go into the exam with experience in harder questions than just hard enough. What band are you aiming for.
Q)

log[x]85=3/2
x^(3/2)=85
x=85^(2/3)

 

[RealiseNothing]

Good you're all set for 100%.

 

[dionb2014]

What is the angle sum of an octagon?
Show working

 

[bleakarcher]

not trying to burst your bubble but isn't maths a little hard to ask over the net?

anyhow

m1 = 2 (given)
m1 * m2 = -1 (product of gradients of perpendicular lines is -1)
2m2=-1
m2=-1/2

:. the gradient of the line perpendicular to y = 2x+ 7 is -1/2

For what values of a is Y=ax a tangent to y= (x^2) - x -2 (sorry i'm not sure if this is school cert standard)?

Let:
y1=ax
y2=x^2-x-2
When y1=y2,
x^2-(a+1)x-2=0
Discriminant=(a+1)^2-4(-2)=a^2+2a+9
In order for the line y=ax to be tangent to the parabola, the discriminant must be 0,
a^2+2a+9=0
Discriminant=2^2-4(9)=-32 which is less than 0
Hence, there are no values for a over R for which the line is tangent to the parabola

 

[RealiseNothing]

What is the angle sum of an octagon?
Show working

180n-360

180*8-360

1440-360

=1080

 

[zombies]

What is the angle sum of an octagon?
Show working

angle sum = 180(n-2)
= 180 (8-2)
= 180 (6)
= 1080

 

[nightweaver066]

Why are people posting questions irrelevant to the SC or even year 10?

 

[bleakarcher]

Why are people posting questions irrelevant to the SC or even year 10?

a) Kite.
b) 62 cm
c) A=(1/2)bh=(1/2)*24*7=84 cm^2
d) i) By the Pythagorean theorem:
AC=sqrt[7^2+24^2]=25 cm
ii) Let the length of BD be x.
(1/2)x*25=2*84
x=[2*2*84]/25=13.44 cm

 

[twinklegal19]

It will obviously be better to go into the exam with experience in harder questions than just hard enough. What band are you aiming for.
Q)

Band 6 of course I agree it's better to experience harder questions before an exam, but SC maths questions are on a whole new level. That's not to say there aren't any odd questions here and there, plus it's easy to get too cocky and make silly mistakes.

 

[ohexploitable]

awwww how cute

 

[bleakarcher]

awwww how cute

What is?

 

[zombies]

What is?

this thread probs