1. **Problem Statement:**
Solve the following vector and scalar operations:
i) $(3 + 2) + (9 + 3)$
ii) $(2xy, 5yg) - (xy, -6y^2)$
iii) $(4, -5) \times (5, -4)$
iv) $(3, 7) \div (3, 2)$
Also, find the additive and multiplicative inverses of:
1) $-7$
2) $\frac{8}{\sqrt{2}}$
3) $3$
4) $0$
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2. **Step-by-step solutions:**
**i) Scalar addition:**
Calculate each sum inside parentheses:
$$3 + 2 = 5$$
$$9 + 3 = 12$$
Now add the results:
$$5 + 12 = 17$$
**ii) Vector subtraction:**
Given vectors $(2xy, 5yg)$ and $(xy, -6y^2)$, subtract component-wise:
$$ (2xy - xy, 5yg - (-6y^2)) = (xy, 5yg + 6y^2) $$
**iii) Vector multiplication (dot product):**
For vectors $(4, -5)$ and $(5, -4)$, the dot product is:
$$4 \times 5 + (-5) \times (-4) = 20 + 20 = 40$$
**iv) Vector division:**
Vector division is not defined in standard vector algebra. However, if interpreted as component-wise division:
$$\left( \frac{3}{3}, \frac{7}{2} \right) = (1, 3.5)$$
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**Additive and multiplicative inverses:**
1) For $-7$:
- Additive inverse is the number which when added gives zero:
$$-7 + 7 = 0$$
So additive inverse is $7$.
- Multiplicative inverse is the number which when multiplied gives one:
$$-7 \times \left(-\frac{1}{7}\right) = 1$$
So multiplicative inverse is $-\frac{1}{7}$.
2) For $\frac{8}{\sqrt{2}}$:
- Additive inverse:
$$-\frac{8}{\sqrt{2}}$$
- Multiplicative inverse:
$$\frac{\sqrt{2}}{8}$$
3) For $3$:
- Additive inverse:
$$-3$$
- Multiplicative inverse:
$$\frac{1}{3}$$
4) For $0$:
- Additive inverse:
$$0$$
- Multiplicative inverse does not exist because division by zero is undefined.
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**Summary:**
- Scalar addition result: $17$
- Vector subtraction result: $(xy, 5yg + 6y^2)$
- Dot product: $40$
- Component-wise division: $(1, 3.5)$
- Additive inverses: $7$, $-\frac{8}{\sqrt{2}}$, $-3$, $0$
- Multiplicative inverses: $-\frac{1}{7}$, $\frac{\sqrt{2}}{8}$, $\frac{1}{3}$, none for $0$
Vector Scalar Operations
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