bac-s-maths 2016 Q4

bac-s-maths · France · caledonie Vectors: Lines & Planes Multi-Step Geometric Modeling Problem
Consider the cube ABCDEFGH represented below. We define the points I and J respectively by $\overrightarrow { \mathrm { HI } } = \frac { 3 } { 4 } \overrightarrow { \mathrm { HG } }$ and $\overrightarrow { \mathrm { JG } } = \frac { 1 } { 4 } \overrightarrow { \mathrm { CG } }$.
  1. On the answer sheet provided in the appendix, to be returned with your work, draw, without justification, the cross-section of the cube by the plane (IJK) where K is a point of the segment [BF].
  2. On the answer sheet provided in the appendix, to be returned with your work, draw, without justification, the cross-section of the cube by the plane (IJL) where L is a point of the line (BF).
  3. Does there exist a point P on the line (BF) such that the cross-section of the cube by the plane (IJP) is an equilateral triangle? Justify your answer.
Consider the cube ABCDEFGH represented below.\\
We define the points I and J respectively by $\overrightarrow { \mathrm { HI } } = \frac { 3 } { 4 } \overrightarrow { \mathrm { HG } }$ and $\overrightarrow { \mathrm { JG } } = \frac { 1 } { 4 } \overrightarrow { \mathrm { CG } }$.

\begin{enumerate}
  \item On the answer sheet provided in the appendix, to be returned with your work, draw, without justification, the cross-section of the cube by the plane (IJK) where K is a point of the segment [BF].
  \item On the answer sheet provided in the appendix, to be returned with your work, draw, without justification, the cross-section of the cube by the plane (IJL) where L is a point of the line (BF).
  \item Does there exist a point P on the line (BF) such that the cross-section of the cube by the plane (IJP) is an equilateral triangle? Justify your answer.
\end{enumerate}