1. Find the next three missing terms of the sequences:
A) Given sequence: 35, 32, 29, 26, _______, _______, _______
- This is an arithmetic sequence where each term decreases by 3.
- Formula for nth term of arithmetic sequence: $$a_n = a_1 + (n-1)d$$ where $d$ is the common difference.
- Here, $d = -3$.
- Next terms:
- 5th term: $26 - 3 = 23$
- 6th term: $23 - 3 = 20$
- 7th term: $20 - 3 = 17$
B) Given sequence: -3, -6, -12, -24, _______, _______, _______
- This is a geometric sequence where each term is multiplied by -2.
- Formula for nth term of geometric sequence: $$a_n = a_1 \times r^{n-1}$$ where $r$ is the common ratio.
- Here, $r = 2$ (absolute value), but signs alternate, so $r = -2$.
- Next terms:
- 5th term: $-24 \times -2 = 48$
- 6th term: $48 \times -2 = -96$
- 7th term: $-96 \times -2 = 192$
2. Difference between arithmetic and geometric patterns:
- Arithmetic pattern: each term changes by adding or subtracting a constant difference.
- Geometric pattern: each term changes by multiplying or dividing by a constant ratio.
3. Identify patterns:
A) 3, 5, 7, ...
- Difference between terms is 2, so arithmetic.
B) 9, -3, -1, -1/3, ...
- Ratios: $-3/9 = -1/3$, $-1/-3 = 1/3$, $-1/3 / -1 = 1/3$ (not consistent ratio), but seems geometric with ratio $-1/3$.
- Actually, check carefully:
- $-3/9 = -1/3$
- $-1/-3 = 1/3$ (not same as previous ratio)
- Since ratio changes, not geometric.
- Differences: $-3 - 9 = -12$, $-1 - (-3) = 2$, not constant.
- Neither arithmetic nor geometric strictly.
C) 10, 0, -10, -20, ...
- Differences: $0 - 10 = -10$, $-10 - 0 = -10$, $-20 - (-10) = -10$
- Constant difference, so arithmetic.
4. Difference between domain and range:
- Domain: set of all possible input values (x-values) of a relation.
- Range: set of all possible output values (y-values) of a relation.
5. Difference between function and relation:
- Relation: any set of ordered pairs.
- Function: a relation where each input (x) has exactly one output (y).
6. Vertical line test:
- A test to determine if a graph represents a function.
- If any vertical line intersects the graph more than once, it is not a function.
7. Identify functions:
A) $F : [0, \infty] \to [0, \infty], f(x) = x^2$
- Not injective on $[0, \infty]$ because $x^2$ is increasing and one-to-one there.
- Surjective onto $[0, \infty]$ because all non-negative values are covered.
- So, $f$ is injective and surjective (bijective) on this domain and codomain.
B) $F : \mathbb{R} \to \mathbb{R}, f(x) = 5x + 1$
- Linear function with slope 5.
- Injective (one-to-one) and surjective (onto) over all real numbers.
- So, bijective.
C) $F : \mathbb{R} \to [0, \infty], f(x) = 4 - x^2$
- Not injective because $f(x) = f(-x)$.
- Surjective onto $[0,4]$ but not onto $[0, \infty]$ since max is 4.
- So, neither injective nor surjective onto $[0, \infty]$.
8. Define quadratic function and example:
- A quadratic function is a polynomial function of degree 2, generally written as $f(x) = ax^2 + bx + c$ where $a \neq 0$.
- Example: $f(x) = 4 - x^2$.
9. Determine domain and range:
A) $R = \{(x,y): y = 3 - x, x = -2, -1, 0, 1, 2\}$
- Domain: $\{-2, -1, 0, 1, 2\}$
- Range: calculate $y$ for each $x$:
- $3 - (-2) = 5$
- $3 - (-1) = 4$
- $3 - 0 = 3$
- $3 - 1 = 2$
- $3 - 2 = 1$
- Range: $\{1, 2, 3, 4, 5\}$
B) $f(x) = \frac{3}{x-1}$
- Domain: all real numbers except $x = 1$ (division by zero undefined).
- Range: all real numbers except $y = 0$ (fraction never zero).
C) $g(x) = \sqrt{2 - x}$
- Domain: $2 - x \geq 0 \Rightarrow x \leq 2$
- Range: $y \geq 0$ (square root outputs non-negative values).
10. Sketch graphs:
A) $R = \{(x,y): y \leq 2x - 1\}$
- Region below or on the line $y = 2x - 1$.
B) $Y = 2x + 4; x = -2, -1, 0, 1, 2$
- Points:
- $x=-2, y=0$
- $x=-1, y=2$
- $x=0, y=4$
- $x=1, y=6$
- $x=2, y=8$
- Plot these points and draw the line.
11. Let $f(x) = 2x - 4$.
i. Find:
A) x-intercept: set $f(x) = 0$
- $2x - 4 = 0 \Rightarrow 2x = 4 \Rightarrow x = 2$
B) y-intercept: set $x = 0$
- $f(0) = 2(0) - 4 = -4$
C) slope: coefficient of $x$ is 2.
ii. Increasing or decreasing?
- Since slope $2 > 0$, function is increasing.
12. Let $f(x) = x - 2$ and $g(x) = 4x^2$.
A) $(f \cdot g)(x) = f(x) \times g(x) = (x - 2)(4x^2) = 4x^3 - 8x^2$
B) $(f \cdot g)(-3) = 4(-3)^3 - 8(-3)^2 = 4(-27) - 8(9) = -108 - 72 = -180$
C) $(g/f)(x) = \frac{g(x)}{f(x)} = \frac{4x^2}{x - 2}$
D) $(g/f)(1) = \frac{4(1)^2}{1 - 2} = \frac{4}{-1} = -4$
13. Given $f(x) = 2x^2 - 3x + 1$ and $g(x) = -x^2 + 2x + 3$.
A) $(2f - g)(x) = 2f(x) - g(x) = 2(2x^2 - 3x + 1) - (-x^2 + 2x + 3)$
- $= 4x^2 - 6x + 2 + x^2 - 2x - 3 = 5x^2 - 8x - 1$
B) $(2f - g)(2) = 5(2)^2 - 8(2) - 1 = 5(4) - 16 - 1 = 20 - 16 - 1 = 3$
14. Given $f(x) = x^2 + 7x + 12$ and $g(x) = \frac{x + 4}{x + 3}$.
Find $\frac{f(x)}{g(x)} = f(x) \times \frac{1}{g(x)} = (x^2 + 7x + 12) \times \frac{x + 3}{x + 4}$
Factor $f(x)$:
- $x^2 + 7x + 12 = (x + 3)(x + 4)$
So,
- $\frac{f(x)}{g(x)} = (x + 3)(x + 4) \times \frac{x + 3}{x + 4} = (x + 3)^2$
Domain excludes $x = -4$ (denominator zero in $g(x)$).
15. Given $f(x) = 8x - \sqrt{8 - x}$, evaluate $f(-8)$.
Calculate:
- $8(-8) = -64$
- $\sqrt{8 - (-8)} = \sqrt{8 + 8} = \sqrt{16} = 4$
So,
- $f(-8) = -64 - 4 = -68$
Final answers summarized:
1A) 23, 20, 17
1B) 48, -96, 192
3A) Arithmetic
3B) Neither strictly arithmetic nor geometric
3C) Arithmetic
7A) Injective and surjective (bijective) on given domain
7B) Bijective
7C) Neither injective nor surjective
9A) Domain: \{-2,-1,0,1,2\}, Range: \{1,2,3,4,5\}
9B) Domain: $x \neq 1$, Range: $y \neq 0$
9C) Domain: $x \leq 2$, Range: $y \geq 0$
11iA) x-intercept: 2
11iB) y-intercept: -4
11iC) slope: 2
11ii) Increasing
12A) $4x^3 - 8x^2$
12B) -180
12C) $\frac{4x^2}{x-2}$
12D) -4
13A) $5x^2 - 8x - 1$
13B) 3
14) $(x + 3)^2$
15) -68
Sequence Patterns Functions
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.