The equation of the directrix of the parabola ${y^2} + 4y + 4x + 2 = 0$ is

The position vectors of $P$ and $Q$ are respectively $\overrightarrow{a}$ and $\overrightarrow{b}$. If $R$ is a point such that $\overrightarrow{PR}=5 \overrightarrow{PQ}$, then the position vector of $R$ is

The work function of a metal is $2 \text{ eV}$. If a radiation of wavelength $3000 \text{ Å}$ is incident on it,the maximum kinetic energy of the emitted photoelectrons is (Planck's constant $h = 6.6 \times 10^{-34} \text{ J s}$; velocity of light $c = 3 \times 10^8 \text{ m/s}$; $1 \text{ eV} = 1.6 \times 10^{-19} \text{ J}$)

If $\int e^x \left( \frac{1-\sin x}{1-\cos x} \right) dx = f(x) + \text{constant}$,then $f(x)$ is equal to

The given graphs $I$,$II$,and $III$ represent general trends observed for different physisorption and chemisorption processes under mild conditions of temperature and pressure. Which of the following statements are correct?

Which of the following statements is incorrect?