For the following questions answer them individually
If $$x^4 + 2x^3 + ax^2 + bx + 9$$ is a perfect square, where a and b are positive real numbers,then the value of a and b are
If $$a^2 + b^2 + c^2 = 16, x^2 + y^2 + z^2 = 25 and ax + by + cz = 20$$, then the value of $$\frac{a + b + c}{x + y + z}$$
The value of x which satisfies the equation $$\frac{x + a^2 + 2c^2}{b + c} + \frac{x + b^2 + 2a^2}{c + a} + \frac{x + c + 2b^2}{a + b} = 0$$ is
$$\triangle ABC$$ is similar to $$\triangle DEF$$. If area of $$\triangle ABC$$ is 9 sq.cm. and area of $$\triangle DEF$$ is 16 sq.cm. and BC = 2.1 cm. Then the length of EF will be
A chord of a circle is equal to its radius. The angle subtended by this chord at a point on the circumference is
Let two chords AB and AC of the larger circle touch the smaller circle having same centre at X and Y. Then XY = ?
Let G be the centroid of the equilateral triangle ABC of perimeter 24 cm. Then the length of AG is
A and B are the centres of two circles with radii 11 cm and 6 cm respectively. A common tangent touches these circles at P & Q respectively. If AB =13 cm, then the length of PQ is
