The sum of two numbers is $6$ times their geometric mean, show that numbers are in the ratio $(3+2 \sqrt{2}):(3-2 \sqrt{2})$
Le the two numbers be $a$ and $b$
$G.M.$ $=\sqrt{a b}$
According to the given condition,
$a+b=6 \sqrt{a b}$ ..........$(1)$
$\Rightarrow(a+b)^{2}=36(a b)$
Also,
$(a-b)^{2}=(a+b)^{2}-4 a b=36 a b-4 a b=32 a b$
$\Rightarrow a-b=\sqrt{32} \sqrt{a b}$
$=4 \sqrt{2} \sqrt{a b}$ .........$(2)$
Adding $(1)$ and $(2),$ we obtain
$2 a=(6+4 \sqrt{2}) \sqrt{a b}$
$a=(3+2 \sqrt{2}) \sqrt{a b}$
Substituting the value of $a$ in $(1),$ we obtain
$b=6 \sqrt{a b}-(3+2 \sqrt{2}) \sqrt{a b}$
$\Rightarrow b=(3-2 \sqrt{2}) \sqrt{a b}$
$\frac{a}{b}=\frac{(3+2 \sqrt{2}) \sqrt{a b}}{(3-2 \sqrt{2}) \sqrt{a b}}=\frac{3+2 \sqrt{2}}{3-2 \sqrt{2}}$
Thus, the required ratio is $(3+2 \sqrt{2}):(3-2 \sqrt{2})$
In a geometric progression, if the ratio of the sum of first $5$ terms to the sum of their reciprocals is $49$, and the sum of the first and the third term is $35$ . Then the first term of this geometric progression is
If the range of $f(\theta)=\frac{\sin ^4 \theta+3 \cos ^2 \theta}{\sin ^4 \theta+\cos ^2 \theta}, \theta \in \mathbb{R}$ is $[\alpha, \beta]$, then the sum of the infinite $G.P.$, whose first term is $64$ and the common ratio is $\frac{\alpha}{\beta}$, is equal to...........
The sum of first four terms of a geometric progression $(G.P.)$ is $\frac{65}{12}$ and the sum of their respective reciprocals is $\frac{65}{18} .$ If the product of first three terms of the $G.P.$ is $1,$ and the third term is $\alpha$, then $2 \alpha$ is ....... .
If ${p^{th}},\;{q^{th}},\;{r^{th}}$ and ${s^{th}}$ terms of an $A.P.$ be in $G.P.$, then $(p - q),\;(q - r),\;(r - s)$ will be in
$0.14189189189….$ can be expressed as a rational number