Top answers


The line L1 has vector equation,  L1 = (  6, 1 ,-1  ) + λ ( 2, 1, 0). The line L2 passes through the points (2, 3, −1) and (4, −1, 1). i) find vector equation of L2 ii)show L2 and L1 are perpendicular.

i)L(r) vector line equations in general are in the form L(r) = p1 + λ (p2) where p1 is any ponit on the line and p2 is the vector direction of the line(unsure how to get the whiteboard up or i would describe...
CE
Answered by Charles E. Maths tutor
8449 Views

The straight line with equation y=3x-7 does not cross or touch the curve with equation y=2px^2-6px+4p, where p is a constant.(a) Show that 4p^2-20p+9<0 (b) Hence find the set of possible values for p.

(a) If we consider the intersection of these two lines then, 3x-7=2px^2-6px+4p.This can be rearranged into the form ax^2+bx+c=0 such that, 2px^2+(-6p-3)x+4p+7, where a=2p, b=-6p-3 and c=4p+7.However, since t...
WG
Answered by Will G. Maths tutor
9355 Views

How do you differentiate using the chain rule?

The chain rule is used where the equation you are looking to differentiate is a function that is itself raised to a power. For example, we might have y = (x 2 -2) 3 and want to differentiate with respect to ...
OB
Answered by Oliver B. Maths tutor
3835 Views

C and D are two events such that P(C) = 0.2, P(D) = 0.6 and P(C|D) = 0.3. Find P(D|C), P(C’ ∩ D’) & P(C’ ∩ D)

Here we use the formula for conditional probability:P(C|D)xP(D)=(𝑃(C∩D))= 0.3x0.6=0.18Note: 𝑃(C∩D)=𝑃(D∩C)=0.18Hence P(D|C)=𝑃(D∩C)/P(C) = 0.18/0.2 = 0.9P(C'∩D') = P(C'|D')xP(D')P(C'|D) = 0.7P(D')=0.4P(C')=0.8...
SV
Answered by Sunny V. Maths tutor
11020 Views

Given that x = cot y, show that dy/dx = -1/(1+x^2)

Identify that we are looking at dy/dx, not dx/dy and realise the relationship that dy/dx=1/(dx/dy)2)Try find dx/dy;cot = 1/tan or (tan) -1 Hence, x=(tan y ) -1 implying dx/dy = (-1)(tan y) -2 (sec 2 y ) =(-1...
JF
Answered by Jacob F. Maths tutor
12719 Views