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3 years ago

Help me plzzzzzzz guyssss

Mathematics

1 answer:

maks197457 [2]3 years ago

5 0

Answer:

1. 75%

2. 20%

3. 20%

4. decrease 5.4%

Step-by-step explanation:

1. 119-68=51, 51/68=0.75

2. 30-24=6, 6/30=0.20

3. 18-15=3, 3/15=0.20

4. 762-721=41, 41/762=0.0538

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$\displaystyle\iint_\sigma\mathbf F\cdot\mathrm dS$
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$\mathbf r_u=\dfrac\partial{\partial u}[2\cos v\,\mathbf i+\sin v\,\mathbf j+u\,\mathbf k]=\mathbf k$
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$\mathbf r_u\times\mathbf r_v=\begin{vmatrix}\mathbf i&\mathbf j&\mathbf k\\0&0&1\\-2\sin v&\cos v&0\end{vmatrix}=-\cos v\,\mathbf i-2\sin v\,\mathbf j$

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$\displaystyle5\int_0^0e^t\,\mathrm dt+5\int_0^{2\pi}(1-\cos2v)\,\mathrm dv$

where $t=-\sin v$ in the first integral, and the half-angle identity is used in the second. The first integral vanishes, leaving you with

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3 years ago