Answer with explanation:
1.
Let a, and b be two numbers between 20 and 5 , which is in geometric progression.
So,the series is as Follows =20 , a, b, 5
Common ratio
[tex]=\frac{\text{Second term}}{\text{First term}}[/tex]
[tex]\frac{20}{a}=\frac{a}{b}=\frac{b}{5}\\\\b^2=5 a---(1)\\\\a^2=20 b\\\\\frac{b^4}{25}=20 b-----\text{Using 1}\\\\b^3=500\\\\b=(500)^{\frac{1}{3}}\\\\b=5\times (4)^{\frac{1}{3}}\\\\5a=25\times (4)^{\frac{2}{3}}\\\\a=5\times (4)^{\frac{2}{3}}[/tex]
2.
44 -32-3
=12-3
=9
3.
⇒Sin (2.4)=Sin(2+0.4)
⇒Sin 2 ×Cos (0.4)+Cos 2 × Sin (0.4)
⇒Sin (A+B)=Sin A×Cos B+Cos A×Sin B
