Question 3(a)
Solve the inequality .

Practise Pure Mathematics 3 techniques for algebra, functions, calculus, vectors and equations through exact and numerical work.
Solve the inequality ∣3x−4∣⩽∣2x+5∣.
Show that the equation log3(2x+1)=1+2log3(x−1) can be written as a quadratic equation in x.
Hence solve the equation log3(4y+1)=1+2log3(2y−1), giving your answer correct to 2 decimal places.
The complex number u is given by u=−1−i3.
Express u in the form r(cosθ+isinθ), where r>0 and −π<θ⩽π. Give the exact values of r and θ.
The complex number v is given by v=5(cos61π+isin61π).
Express the complex number uv in the form reiθ where r>0 and −π<θ⩽π.
The polynomial p(x) is defined by
Find the quotient when p(x) is divided by (x2+3) and show that the remainder is -11.

The diagram shows the curve with equation y=8e−21x−1. The curve meets the axes at the points A and B. The shaded region is bounded by the curve and the line segment AB.
Show that the x-coordinate of B is 6ln2.
Find the area of the shaded region. Give your answer in the form pln2−q, where p and q are positive integers.
Given that ∫aa+143x1 dx=ln2, find the value of the positive constant a.
The equation of a curve is y=tan−1(4x).
Find the exact values of x when the gradient of the curve is 41.
Find the exact value of ∫00.25ydx.
The polynomial p(x) is defined by
where k is a constant. It is given that (x+2) is a factor of p(x).
Find the value of k.
It is given that the equation p(x)=0 has exactly two real roots, denoted by α and β, where α is an integer and β is not an integer.
State the value of α and show that β satisfies the equation x=3−2x−4.5.
Show by calculation that −1.4<β<−1.0.
Use an iterative formula, based on the equation in part (b), to find the value of β correct to 3 significant figures. Give the result of each iteration to 5 significant figures.
The polynomials f(x) and g(x) are defined by
where a and b are constants.
Given that (x+3) is a factor of f(x), find the value of a.
Given that the remainder is 40 when g(x) is divided by (x-2), find the value of b.
Hence solve the equation f(cosecθ)−g(cosecθ)=0 for 0<θ<2π.
The diagram shows a tank for holding water. The tank is in the shape of a cube of side 50 cm. At time t seconds, the depth of water in the tank is h cm. Water is poured into the tank at a rate of 5000 cm3 s−1. Water pours out of the tank through a hole in the bottom at a rate proportional to h2.
When h=20, the depth of the water is increasing at a rate of 0.4cms−1.
Show that dtdh=250500−h2.
Given that h=0 when t=0, find the time taken for the depth of the water in the tank to reach 20 cm.