JEE Advance - Mathematics (2024 - Paper 2 Online - No. 7)
Explanation
Equation of tangent at (2t$$^2$$, 4t) is
$$\mathrm{ty}=\mathrm{x}+2 \mathrm{t}^2$$
$$\because$$ It is passing through $$(-4,0)$$
$$\therefore 0=-4+2 \mathrm{t}^2 \Rightarrow \mathrm{t}= \pm \sqrt{2}$$
$$\left.\begin{array}{rl} \therefore & \mathrm{A}_1=(4,4 \sqrt{2}) \\ & \mathrm{B}_1=(4,-4 \sqrt{2}) \end{array}\right\} \quad \begin{aligned} & \mathrm{OA}_1=\sqrt{48}=4 \sqrt{3} \\ & \mathrm{~A}_1 \mathrm{~B}_1=8 \sqrt{2} \end{aligned}$$
Equation of altitude of $$\Delta A_1 B_1 C_1$$ drawn from $$A_1$$ is
$$\begin{aligned} & y-4 \sqrt{2}=\sqrt{2}(x-4) \\ & \Rightarrow \sqrt{2} x-y=0 \quad \text{... (1)} \end{aligned}$$
Equation of altitude of $$\Delta A_1 B_1 C_1$$ drawn from $$C_1$$ is
$$\mathrm{x}=0\quad \text{... (2)}$$
Solving (1) and (2) $$\Rightarrow$$ orthocentre is $$(0,0)$$
$$\therefore$$ correct options are (A), (C)
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