Pure- Equations and Inequalities (3) Flashcards
How can linear simultaneous equation be solved?
Elimination or substitution
How many solutions do simultaneous equations with one quadratic and one linear have?
Two pairs of solutions
What do the solutions to simultaneous equations represent?
The intersections of their graphs
What is the solution of an inequality?
The set of all real numbers that make the inequality true.
What is the set notation for x>2 and x<=4?
{x:-2-2} ⋂ {x:x<=4}
What does ⋂ mean?
Intersection ie. objects in set A and set B
What is the set notation for x<=-1 or x>3?
{x:x<=-1} ⋃ {x:x>3}
What does ⋃ mean?
Union ie.objects in set A or set B
How do you solve a quadratic inequality?
- Rearrange so RHS=0
- Solve corresponding quadratic to find critical values
- Sketch graph of quadratic function
- Use sketch to find required set of values
If y>f(x) or y
As a dotted line
If y>=f(x) or y<=f(x) how is the curve drawn?
As a solid line
If y=f(x) is below the curve y=g(x) which inequality is used?
f(x)
If y=f(x) is above the curve y=g(x) which inequality is used?
f(x)>g(x)