2.3 Exercises
From Förberedande kurs i matematik 1
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| style="border-bottom:1px solid #000" width="5px" | | | style="border-bottom:1px solid #000" width="5px" | | ||
- | {{ | + | {{Not selected tab|[[2.3 Quadratic expressions|Theory]]}} |
- | {{ | + | {{Selected tab|[[2.3 Exercises|Exercises]]}} |
| style="border-bottom:1px solid #000" width="100%"| | | style="border-bottom:1px solid #000" width="100%"| | ||
|} | |} | ||
- | === | + | ===Exercise 2.3:1=== |
<div class="ovning"> | <div class="ovning"> | ||
- | + | Complete the square of the expressions | |
{| width="100%" cellspacing="10px" | {| width="100%" cellspacing="10px" | ||
|a) | |a) | ||
Line 20: | Line 20: | ||
|width="25%" | <math>x^2+5x+3</math> | |width="25%" | <math>x^2+5x+3</math> | ||
|} | |} | ||
- | </div>{{#NAVCONTENT: | + | </div>{{#NAVCONTENT:Answer|Answer 2.3:1|Solution a|Solution 2.3:1a|Solution b|Solution 2.3:1b|Solution c|Solution 2.3:1c|Solution d|Solution 2.3:1d}} |
- | === | + | ===Exercise 2.3:2=== |
<div class="ovning"> | <div class="ovning"> | ||
- | + | Solve the following second order equations by completing the square | |
{| width="100%" cellspacing="10px" | {| width="100%" cellspacing="10px" | ||
|a) | |a) | ||
Line 40: | Line 40: | ||
|width="33%" | <math>3x^2-10x+8=0</math> | |width="33%" | <math>3x^2-10x+8=0</math> | ||
|} | |} | ||
- | </div>{{#NAVCONTENT: | + | </div>{{#NAVCONTENT:Answer|Answer 2.3:2|Solution a|Solution 2.3:2a|Solution b|Solution 2.3:2b|Solution c|Solution 2.3:2c|Solution d|Solution 2.3:2d|Solution e|Solution 2.3:2e|Solution f|Solution 2.3:2f}} |
- | === | + | ===Exercise 2.3:3=== |
<div class="ovning"> | <div class="ovning"> | ||
- | + | Solve the following equations directly | |
{| width="100%" cellspacing="10px" | {| width="100%" cellspacing="10px" | ||
|a) | |a) | ||
Line 61: | Line 61: | ||
|width="50%" | <math>x(x^2-2x)+x(2-x)=0</math> | |width="50%" | <math>x(x^2-2x)+x(2-x)=0</math> | ||
|} | |} | ||
- | </div>{{#NAVCONTENT: | + | </div>{{#NAVCONTENT:Answer|Answer 2.3:3|Solution a|Solution 2.3:3a|Solution b|Solution 2.3:3b|Solution c|Solution 2.3:3c|Solution d|Solution 2.3:3d|Solution e|Solution 2.3:3e|Solution f|Solution 2.3:3f}} |
- | === | + | ===Exercise 2.3:4=== |
<div class="ovning"> | <div class="ovning"> | ||
- | + | Find a second-degree equation which has roots | |
{| width="100%" cellspacing="10px" | {| width="100%" cellspacing="10px" | ||
|a) | |a) | ||
- | |width="100%" | <math>-1\ </math> | + | |width="100%" | <math>-1\ </math> and <math>\ 2</math> |
|- | |- | ||
|b) | |b) | ||
- | |width="100" | <math>1+\sqrt{3}\ </math> | + | |width="100" | <math>1+\sqrt{3}\ </math> and <math>\ 1-\sqrt{3}</math> |
|- | |- | ||
|c) | |c) | ||
- | |width="100" | <math>3\ </math> | + | |width="100" | <math>3\ </math> and <math>\ \sqrt{3}</math> |
|} | |} | ||
- | </div>{{#NAVCONTENT: | + | </div>{{#NAVCONTENT:Answer|Answer 2.3:4|Solution a|Solution 2.3:4a|Solution b|Solution 2.3:4b|Solution c|Solution 2.3:4c}} |
+ | |||
+ | ===Exercise 2.3:5=== | ||
+ | <div class="ovning"> | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="100%" | Find a second-degree equation which only has <math>\,-7\,</math> as a root. | ||
+ | |- | ||
+ | |b) | ||
+ | |width="100" | Determine a value of <math>\,x\,</math> which makes the expression <math>\,4x^2-28x+48\,</math> negative. | ||
+ | |- | ||
+ | |c) | ||
+ | |width="100" | The equation <math>\,x^2+4x+b=0\,</math> has one root at <math>\,x=1\,</math>. Determine the value of the constant <math>\,b\,</math>. | ||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:5|Solution a|Solution 2.3:5a|Solution b|Solution 2.3:5b|Solution c|Solution 2.3:5c}} | ||
+ | |||
+ | ===Exercise 2.3:6=== | ||
+ | <div class="ovning"> | ||
+ | Determine the smallest value that the following polynomials can take | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="33%" | <math>x^2-2x+1</math> | ||
+ | |b) | ||
+ | |width="33%" | <math>x^2-4x+2</math> | ||
+ | |c) | ||
+ | |width="33%" | <math>x^2-5x+7</math>. | ||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:6|Solution a|Solution 2.3:6a|Solution b|Solution 2.3:6b|Solution c|Solution 2.3:6c}} | ||
+ | |||
+ | |||
+ | ===Exercise 2.3:7=== | ||
+ | <div class="ovning"> | ||
+ | Determine the largest value that the following polynomials can take | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="33%" | <math>1-x^2</math> | ||
+ | |b) | ||
+ | |width="33%" | <math>-x^2+3x-4</math> | ||
+ | |c) | ||
+ | |width="33%" | <math>x^2+x+1</math>. | ||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:7|Solution a|Solution 2.3:7a|Solution b|Solution 2.3:7b|Solution c|Solution 2.3:7c}} | ||
+ | |||
+ | ===Exercise 2.3:8=== | ||
+ | <div class="ovning"> | ||
+ | Sketch the graph of the following functions | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="33%" | <math>f(x)=x^2+1</math> | ||
+ | |b) | ||
+ | |width="33%" | <math>f(x)=(x-1)^2+2</math> | ||
+ | |c) | ||
+ | |width="33%" | <math>f(x)=x^2-6x+11</math>. | ||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:8|Solution a|Solution 2.3:8a|Solution b|Solution 2.3:8b|Solution c|Solution 2.3:8c}} | ||
+ | |||
+ | ===Exercise 2.3:9=== | ||
+ | <div class="ovning"> | ||
+ | Find all the points where the following curves intersect the <math>x</math>-axis. | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="33%" | <math>y=x^2-1</math> | ||
+ | |b) | ||
+ | |width="33%" | <math>y=x^2-5x+6</math> | ||
+ | |c) | ||
+ | |width="33%" | <math>y=3x^2-12x+9</math> | ||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:9|Solution a|Solution 2.3:9a|Solution b|Solution 2.3:9b|Solution c|Solution 2.3:9c}} | ||
+ | |||
+ | ===Exercise 2.3:10=== | ||
+ | <div class="ovning"> | ||
+ | In the ''xy''-plane, shade in the area whose coordinates <math>\,(x,y)\,</math> satisfy | ||
+ | {| width="100%" cellspacing="10px" | ||
+ | |a) | ||
+ | |width="50%" | <math>y \geq x^2\ </math> and <math>\ y \leq 1 </math> | ||
+ | |b) | ||
+ | |width="50%" | <math>y \leq 1-x^2\ </math> and <math>\ x \geq 2y-3 </math> | ||
+ | |- | ||
+ | |c) | ||
+ | |width="50%" | <math>1 \geq x \geq y^2</math> | ||
+ | |d) | ||
+ | |width="50%" | <math>x^2 \leq y \leq x </math> | ||
+ | |||
+ | |} | ||
+ | </div>{{#NAVCONTENT:Answer|Answer 2.3:10|Solution a|Solution 2.3:10a|Solution b|Solution 2.3:10b|Solution c|Solution 2.3:10c|Solution d|Solution 2.3:10d}} |
Current revision
Theory | Exercises |
Exercise 2.3:1
Complete the square of the expressions
a) | \displaystyle x^2-2x | b) | \displaystyle x^2+2x-1 | c) | \displaystyle 5+2x-x^2 | d) | \displaystyle x^2+5x+3 |
Answer
Solution a
Solution b
Solution c
Solution d
Exercise 2.3:2
Solve the following second order equations by completing the square
a) | \displaystyle x^2-4x+3=0 | b) | \displaystyle y^2+2y-15=0 | c) | \displaystyle y^2+3y+4=0 |
d) | \displaystyle 4x^2-28x+13=0 | e) | \displaystyle 5x^2+2x-3=0 | f) | \displaystyle 3x^2-10x+8=0 |
Answer
Solution a
Solution b
Solution c
Solution d
Solution e
Solution f
Exercise 2.3:3
Solve the following equations directly
a) | \displaystyle x(x+3)=0 | b) | \displaystyle (x-3)(x+5)=0 |
c) | \displaystyle 5(3x-2)(x+8)=0 | d) | \displaystyle x(x+3)-x(2x-9)=0 |
e) | \displaystyle (x+3)(x-1)-(x+3)(2x-9)=0 | f) | \displaystyle x(x^2-2x)+x(2-x)=0 |
Answer
Solution a
Solution b
Solution c
Solution d
Solution e
Solution f
Exercise 2.3:4
Find a second-degree equation which has roots
a) | \displaystyle -1\ and \displaystyle \ 2 |
b) | \displaystyle 1+\sqrt{3}\ and \displaystyle \ 1-\sqrt{3} |
c) | \displaystyle 3\ and \displaystyle \ \sqrt{3} |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:5
a) | Find a second-degree equation which only has \displaystyle \,-7\, as a root. |
b) | Determine a value of \displaystyle \,x\, which makes the expression \displaystyle \,4x^2-28x+48\, negative. |
c) | The equation \displaystyle \,x^2+4x+b=0\, has one root at \displaystyle \,x=1\,. Determine the value of the constant \displaystyle \,b\,. |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:6
Determine the smallest value that the following polynomials can take
a) | \displaystyle x^2-2x+1 | b) | \displaystyle x^2-4x+2 | c) | \displaystyle x^2-5x+7. |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:7
Determine the largest value that the following polynomials can take
a) | \displaystyle 1-x^2 | b) | \displaystyle -x^2+3x-4 | c) | \displaystyle x^2+x+1. |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:8
Sketch the graph of the following functions
a) | \displaystyle f(x)=x^2+1 | b) | \displaystyle f(x)=(x-1)^2+2 | c) | \displaystyle f(x)=x^2-6x+11. |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:9
Find all the points where the following curves intersect the \displaystyle x-axis.
a) | \displaystyle y=x^2-1 | b) | \displaystyle y=x^2-5x+6 | c) | \displaystyle y=3x^2-12x+9 |
Answer
Solution a
Solution b
Solution c
Exercise 2.3:10
In the xy-plane, shade in the area whose coordinates \displaystyle \,(x,y)\, satisfy
a) | \displaystyle y \geq x^2\ and \displaystyle \ y \leq 1 | b) | \displaystyle y \leq 1-x^2\ and \displaystyle \ x \geq 2y-3 |
c) | \displaystyle 1 \geq x \geq y^2 | d) | \displaystyle x^2 \leq y \leq x |
Answer
Solution a
Solution b
Solution c
Solution d