Determine whether the given function is one-to-one. If it is one-to-one, find a formula for the \( f(x)=\sqrt{x-9} \) A. \( f^{-1}(x)=(x-9)^{2} \) B. \( f^{-1}(x)=x^{2}+9, x \geq 0 \) C. \( f^{-1}(x)=\sqrt{x+9} \) D. Not one-to-one

257. Funksiýalaryň grafigini guruñ: \( \begin{array}{ll}\text { a) } y=x^{2}+6 x ; & \text { c) } y=0,5 x^{2}-4 \\ \text { b) } y=-\frac{1}{2} x^{2}+2 ; & \text { d) } y=\frac{1}{2} x^{2}-3 x\end{array} \)

Determine la forma polar del complejo \( z=-3-\sqrt{3} i \)

Постройте график функции и укажите для нее область определения и значения \( x \), при которых \( y>0 \). а) \( у=3 \mathrm{x}^{-3} \);

Find \( \|\mathbf{v}\| \). \( \begin{array}{l}\mathbf{v}=9 \mathbf{i}-12 \mathbf{j} \\ \|\mathbf{v}\|=\square \text { (Type an exact answer, using radicals as needed. Simplify your answer.) }\end{array} \)

Find the direction angle of \( v \) for the following vector. \( v=2 i-4 j \) What is the direction angle of \( v \) ? TRound to one decimal place as needed.)