Sign in
Please select an account to continue using cracku.in
↓ →
Join Our JEE Preparation Group
Prep with like-minded aspirants; Get access to free daily tests and study material.
If the orthocentre of the triangle, whose vertices are $$1, 2$$, $$2, 3$$ and $$3, 1$$ is $$\alpha, \beta$$, then the quadratic equation whose roots are $$\alpha + 4\beta$$ and $$4\alpha + \beta$$, is
Given vertices: $$A(1, 2)$$, $$B(2, 3)$$, $$C(3, 1)$$.
To find the orthocenter, we need the intersection of any two altitudes.
Altitude from C perpendicular to AB:
Slope of AB = $$\frac{3-2}{2-1} = 1$$. So slope of altitude from C = $$-1$$.
Equation: $$y - 1 = -1(x - 3) \Rightarrow y = -x + 4$$ ... (i)
Altitude from A perpendicular to BC:
Slope of BC = $$\frac{1-3}{3-2} = -2$$. So slope of altitude from A = $$\frac{1}{2}$$.
Equation: $$y - 2 = \frac{1}{2}(x - 1) \Rightarrow y = \frac{x}{2} + \frac{3}{2}$$ ... (ii)
Solving (i) and (ii):
$$ -x + 4 = \frac{x}{2} + \frac{3}{2} $$ $$ -\frac{3x}{2} = -\frac{5}{2} $$ $$ x = \frac{5}{3}, \quad y = -\frac{5}{3} + 4 = \frac{7}{3} $$So the orthocenter is $$(\alpha, \beta) = \left(\frac{5}{3}, \frac{7}{3}\right)$$.
Now finding the roots of the quadratic:
$$ \alpha + 4\beta = \frac{5}{3} + \frac{28}{3} = \frac{33}{3} = 11 $$ $$ 4\alpha + \beta = \frac{20}{3} + \frac{7}{3} = \frac{27}{3} = 9 $$Sum of roots = $$11 + 9 = 20$$
Product of roots = $$11 \times 9 = 99$$
The quadratic equation is:
$$ x^2 - 20x + 99 = 0 $$Create a FREE account and get:
Predict your JEE Main percentile, rank & performance in seconds
Educational materials for JEE preparation
Ask our AI anything
AI can make mistakes. Please verify important information.
AI can make mistakes. Please verify important information.