1. **Problem:** Given the function $d(s) = s^2 + 0 = d(s) = s = s$, find $d(1)$.
Step 1: Simplify the function: $d(s) = s^2$.
Step 2: Substitute $s=1$: $d(1) = 1^2 = 1$.
2. **Problem:** Find the domain of the function $d(s) = s$.
Step 1: The function $d(s) = s$ is a linear function defined for all real numbers.
Step 2: Therefore, the domain is $(-\infty, \infty)$.
3. **Problem:** If $d$ is an odd function, find $-1 - d(1)$.
Step 1: For an odd function, $d(-1) = -d(1)$.
Step 2: Calculate $-1 - d(1)$. Since $d(-1) = -d(1)$, then $-1 - d(1) = d(-1) - 1$.
Step 3: Without specific values, the expression remains $-1 - d(1)$.
4. **Problem:** Determine the parity of the function $d(s) = s \cos s$.
Step 1: $s$ is an odd function, $\cos s$ is an even function.
Step 2: The product of an odd and even function is odd.
Step 3: Therefore, $d(s)$ is an odd function.
5. **Problem:** Identify which relation is not a function among:
- $2y = \cos x$
- $y = x - 1$
- $5y = x + 3 + 1$
Step 1: Solve each for $y$.
- $y = \frac{\cos x}{2}$ (function)
- $y = x - 1$ (function)
- $y = \frac{x + 4}{5}$ (function)
Step 2: All are functions since each $x$ corresponds to exactly one $y$.
6. **Problem:** Triangle $ABC$ with $AB=90$, angle $B D = 45$, and circumradius $7$ cm. Find the perimeter.
Step 1: Use the formula for perimeter $P = 2R \times \text{sum of sines of angles}$.
Step 2: Given data insufficient for exact calculation; assuming right triangle with hypotenuse $2R=14$.
Step 3: Perimeter approximately $20$ cm (closest option).
7. **Problem:** In triangle $MBJ$, given $MB = \sin M'$, $\sin B'$, $\sin J' = \sin M$, find the perimeter of the circumcircle.
Step 1: The perimeter of the circumcircle is $2\pi R$.
Step 2: Given the problem, the answer is $\pi$.
Math Questions
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