- ✓$\frac{{19}}{2}$
- B$9$
- C$8$
- D$\frac{{17}}{2}$
$\vec{a} \times \vec{c}+\vec{b}=0$
$ \Rightarrow \left| {\begin{array}{*{20}{c}}
{\hat i}&{\hat j}&{\hat k}\\
1&{ - 1}&0\\
x&y&z
\end{array}} \right|$
$+(\hat{i}+\hat{\bar{j}}+\hat{k})=0$
$\hat{i}(-z)-\hat{j}(z)+\hat{k}(y+x)$
$\Rightarrow 1-z=0 \Rightarrow z=1$
$\text { Also } x+y=-1, \text { and } \vec{a} \cdot \vec{c}=4 \Rightarrow x-y=4$
$\Rightarrow x=\frac{3}{2}, y=\frac{5}{2}$
$\therefore|\overrightarrow{\mathrm{c}}|^{2}=x^{2}+y^{2}+z^{2}$
$=\frac{9}{4}+\frac{25}{4}+1=\frac{38}{4}=\frac{19}{2}$
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$f(x)=\left\{\begin{array}{ll} \min \left\{(x+6), x^{2}\right\}, & -3 \leq x \leq 0 \\ \max \left\{\sqrt{x}, x^{2}\right\}, & 0 \leq x \leq 1 \end{array}\right.$ આપેલ છે.
જો $y = f ( x )$ અને $x$ -અક્ષ દ્વારા આવૃત પ્રદેશનું ક્ષેત્રફળ $A$ હોય તો $6 A$ ની કિમંત મેળવો.