Top answers

The parametric equations of a curve are: x = cos2θ y = sinθcosθ. Find the cartesian form of the equation.

x = cos2θ y = sinθcosθcos2θ = cos 2 θ - sin 2 θ cos 2 θ + sin 2 θ = 12cos 2 θ = 1 + cos2θ cos 2 θ = 1/2(1 + x)2sin 2 θ = 1 - cos2θ sin 2 θ = 1/2 (1 - x)y 2 = sin 2 θcos 2 θy 2 = ( 1/2(1 + x)) . (1/2 (1 - x))...
AN
Answered by Amelia N. • Maths tutor
8979 Views

find dy/dx of x^1/2 + 4/(x^1/2) + 4

This can be rewritten as x 1/2 + 4x -1/2 + 4, hence dy/dx = (1/2)x -1/2 - 2x -3/2
OO
Answered by Olufayojimi O. • Maths tutor
3750 Views

What is the best way to structure answers to evaluation questions (24 marks)?

For longer answer questions, examiners want to see you demonstrate a higher level of analysis and evaluation. The short mark answers rely solely on knowledge but the longer marks require you to do more with ...
KP
Answered by Kajal P. • Geography tutor
32646 Views

(a) By using a suitable trigonometrical identity, solve the equation tan(2x-π/6)^2 =11-sec(2x-π/6)giving all values of x in radians to two decimal places in the interval 0<=x <=π .

say (2x-π/6)=qtan 2 q = sec 2 q-1so sec 2 q-1= 11 - sec q sec 2 q + sec q -12 = 0(sec q -3) (sec q + 4) = 0sec q = 3 or -4because 0&lt;=x&lt;= πso -π/6 &lt;= q &lt;= 11π/6q = 1.23 or 1.82 or 4.46 or 5.05so x...
ZZ
Answered by Zhaohui Z. • Maths tutor
9214 Views

Describe the changes in equilibrium of ethanol production from ethene and water (enthalpy of reaction is ∆H = - 46 kJ/mol) when: (a) a high pressure is applied; (b) ethanol concentration is increased; (c) temperature is increased; (d) a catalyst is used.

The equation for the reaction (would be given for this type of question but I ran out of space): C 2 H 4 (g) + H 2 O (g) ⇌ C 2 H 5 OH (g) ∆H = - 46 kJ/molQuestion is based on Le Chatelier's principle: if a s...
AA
Answered by Aiste A. • Chemistry tutor
8644 Views