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#### Resources tagged with Quadratic equations similar to Three by One:

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##### Other tags that relate to Three by One
Vector algebra. Curious. Cosine. Complex numbers. Argand diagram. Quadratic equations. smartphone. Sine. Interactivities. Tangent.

### Conjugate Tracker

##### Stage: 5 Challenge Level:

Make a conjecture about the curved track taken by the complex roots of a quadratic equation and use complex conjugates to prove your conjecture.

### Roots and Coefficients

##### Stage: 5 Challenge Level:

If xyz = 1 and x+y+z =1/x + 1/y + 1/z show that at least one of these numbers must be 1. Now for the complexity! When are the other numbers real and when are they complex?

### Partly Circles

##### Stage: 4 Challenge Level:

What is the same and what is different about these circle questions? What connections can you make?

### Complex Sine

##### Stage: 5 Challenge Level:

Solve the equation sin z = 2 for complex z. You only need the formula you are given for sin z in terms of the exponential function, and to solve a quadratic equation and use the logarithmic function.

### Golden Thoughts

##### Stage: 4 Challenge Level:

Rectangle PQRS has X and Y on the edges. Triangles PQY, YRX and XSP have equal areas. Prove X and Y divide the sides of PQRS in the golden ratio.

### Interactive Number Patterns

##### Stage: 4 Challenge Level:

How good are you at finding the formula for a number pattern ?

### How Old Am I?

##### Stage: 4 Challenge Level:

In 15 years' time my age will be the square of my age 15 years ago. Can you work out my age, and when I had other special birthdays?

### Golden Fibs

##### Stage: 5 Challenge Level:

When is a Fibonacci sequence also a geometric sequence? When the ratio of successive terms is the golden ratio!

### Pareq Calc

##### Stage: 4 Challenge Level:

Triangle ABC is an equilateral triangle with three parallel lines going through the vertices. Calculate the length of the sides of the triangle if the perpendicular distances between the parallel. . . .

### Golden Mathematics

##### Stage: 5

A voyage of discovery through a sequence of challenges exploring properties of the Golden Ratio and Fibonacci numbers.

##### Stage: 5 Short Challenge Level:

Can you solve this problem involving powers and quadratics?

### A Third of the Area

##### Stage: 4 Short Challenge Level:

The area of the small square is $\frac13$ of the area of the large square. What is $\frac xy$?

### Weekly Challenge 39: Symmetrically So

##### Stage: 5 Challenge Level:

Exploit the symmetry and turn this quartic into a quadratic.

##### Stage: 5 Challenge Level:

Can you find a quadratic equation which passes close to these points?

### Xtra

##### Stage: 4 and 5 Challenge Level:

Find the sides of an equilateral triangle ABC where a trapezium BCPQ is drawn with BP=CQ=2 , PQ=1 and AP+AQ=sqrt7 . Note: there are 2 possible interpretations.

### Implicitly

##### Stage: 5 Challenge Level:

Can you find the maximum value of the curve defined by this expression?

### Polar Flower

##### Stage: 5 Challenge Level:

This polar equation is a quadratic. Plot the graph given by each factor to draw the flower.

### Proof Sorter - Quadratic Equation

##### Stage: 4 and 5 Challenge Level:

This is an interactivity in which you have to sort the steps in the completion of the square into the correct order to prove the formula for the solutions of quadratic equations.

### Target Six

##### Stage: 5 Challenge Level:

Show that x = 1 is a solution of the equation x^(3/2) - 8x^(-3/2) = 7 and find all other solutions.

### Always Two

##### Stage: 4 and 5 Challenge Level:

Find all the triples of numbers a, b, c such that each one of them plus the product of the other two is always 2.

### Halving the Triangle

##### Stage: 5 Challenge Level:

Draw any triangle PQR. Find points A, B and C, one on each side of the triangle, such that the area of triangle ABC is a given fraction of the area of triangle PQR.

### Golden Ratio

##### Stage: 5 Challenge Level:

Solve an equation involving the Golden Ratio phi where the unknown occurs as a power of phi.

### Pentakite

##### Stage: 4 and 5 Challenge Level:

ABCDE is a regular pentagon of side length one unit. BC produced meets ED produced at F. Show that triangle CDF is congruent to triangle EDB. Find the length of BE.

### Two Cubes

##### Stage: 4 Challenge Level:

Two cubes, each with integral side lengths, have a combined volume equal to the total of the lengths of their edges. How big are the cubes? [If you find a result by 'trial and error' you'll need to. . . .

### Darts and Kites

##### Stage: 4 Challenge Level:

Explore the geometry of these dart and kite shapes!

### Cocked Hat

##### Stage: 5 Challenge Level:

Sketch the graphs for this implicitly defined family of functions.

### In Between

##### Stage: 5 Challenge Level:

Can you find the solution to this algebraic inequality?

### Good Approximations

##### Stage: 5 Challenge Level:

Solve quadratic equations and use continued fractions to find rational approximations to irrational numbers.

### Kissing

##### Stage: 5 Challenge Level:

Two perpendicular lines are tangential to two identical circles that touch. What is the largest circle that can be placed in between the two lines and the two circles and how would you construct it?

### Continued Fractions II

##### Stage: 5

In this article we show that every whole number can be written as a continued fraction of the form k/(1+k/(1+k/...)).

### Pent

##### Stage: 4 and 5 Challenge Level:

The diagram shows a regular pentagon with sides of unit length. Find all the angles in the diagram. Prove that the quadrilateral shown in red is a rhombus.

### Bird-brained

##### Stage: 5 Challenge Level:

How many eggs should a bird lay to maximise the number of chicks that will hatch? An introduction to optimisation.

### Square Mean

##### Stage: 4 Challenge Level:

Is the mean of the squares of two numbers greater than, or less than, the square of their means?

### Golden Construction

##### Stage: 5 Challenge Level:

Draw a square and an arc of a circle and construct the Golden rectangle. Find the value of the Golden Ratio.

### Resistance

##### Stage: 5 Challenge Level:

Find the equation from which to calculate the resistance of an infinite network of resistances.

### Golden Eggs

##### Stage: 5 Challenge Level:

Find a connection between the shape of a special ellipse and an infinite string of nested square roots.

##### Stage: 5 Challenge Level:

Find all real solutions of the equation (x^2-7x+11)^(x^2-11x+30) = 1.

### How Many Balls?

##### Stage: 5 Challenge Level:

A bag contains red and blue balls. You are told the probabilities of drawing certain combinations of balls. Find how many red and how many blue balls there are in the bag.

### Plus or Minus

##### Stage: 5 Challenge Level:

Make and prove a conjecture about the value of the product of the Fibonacci numbers $F_{n+1}F_{n-1}$.