Let $P\left(\frac{1}{p}, \frac{1}{q}\right)$ and $Q\left(\frac{1}{q}, \frac{1}{p}\right)$ be points on the hyperbola $y=\frac{1}{x}$ with $p>q>0$ - HSC - SSCE Mathematics Extension 2 - Question 8 - 2004 - Paper 1
Question 8
Let $P\left(\frac{1}{p}, \frac{1}{q}\right)$ and $Q\left(\frac{1}{q}, \frac{1}{p}\right)$ be points on the hyperbola $y=\frac{1}{x}$ with $p>q>0$. Let $P'$ be the po... show full transcript
Worked Solution & Example Answer:Let $P\left(\frac{1}{p}, \frac{1}{q}\right)$ and $Q\left(\frac{1}{q}, \frac{1}{p}\right)$ be points on the hyperbola $y=\frac{1}{x}$ with $p>q>0$ - HSC - SSCE Mathematics Extension 2 - Question 8 - 2004 - Paper 1
Step 1
Find the area of triangle $OPP'$
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The area of triangle is given by the formula:
Area=21×base×height
Here, the base is the segment OP′ and the height is the y-coordinate of point P.
Let the coordinates of points be O(0,0), P(p,q), and P′(p,0). Therefore, the area can be calculated as:
AreaOPP′=21×p×q=2pq
Step 2
Prove that the area of the shaded region $OPQ$ is equal to the area of the shaded region $Q'QP'$
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
To prove this, we can compare the two areas by utilizing the previously calculated area of triangle OPP′. Since the regions are symmetric about the line y=x, the areas can be shown to be equal through integration or geometric analysis. The area can be evaluated using the hyperbola's properties and the coordinates of points O, P, and Q.
Step 3
By using similar triangles, or otherwise, prove that $r^{2}=pq$
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
By constructing triangles OMP and R′RQ, we can establish relationships between their sides using the concept of similar triangles. The segments related to r, p, and q yield the equation:
r2=pimesq using properties of proportional lengths in similar triangles.
Step 4
By using integration, or otherwise, show that the line $RR'$ divides the shaded region $Q'QP'P$ into two pieces of equal area
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
By integrating the area under the curve bounded by lines QR′ and Q′P′ from the coordinates of Q and R′, we can find the area of the section. The integral bounds will be from q to the intersection point of the lines. By computing the area, it can be shown that this area is equal to half of the shaded region Q′QP′P.
Step 5
Deduce that the line $OR$ divides the shaded region $OPQ$ into two pieces of equal area
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Using the previously established symmetry in the shape of the regions and the proven area equality, it can be deduced that the line OR bisects the area of the triangular region OPQ, thereby confirming that the areas on either side of line OR are equal.