JEE Class main Answered
suppose a is a positive real number such that 
then
a) 
<2
b)2< <3
c)3< <4
d)4<=
Asked by Girijeshpandey.rjil | 28 Mar, 2019, 06:20: PM
Expert Answer
f(a) = a5 -a3 +a -2
if a =1, f(1) = -1 ; if a=2, f(2) = 24 ; hence root of f(a) is between 1 and 2 , i.e., 1< a <2
let us check middle value for root. let a = 3/2, f(3/2) = (243/32) -(27/8) +(3/2) -2 = 119/32 or f(a) >3
let us check middle value between 1 and 1.5, let a = 1.25 = 5/4, f(5/4) = (3125/1024) -(125/64) +(5/4) -2 ≈ 0.4
hence the root is near to 1.25. Let us consider a = 1+Δa , where Δa ≈ 0.25
then a6 = (1+Δa)6 ≈ 1+ 6C1 Δa + 6C2 (Δa)2 ..................................(1)
[ powers of Δa3 and higher orders are neglected in eqn.(1) ]
substituting Δa in eqn.(1), we get, a6 ≈ (1+0.25)6 ≈ 1 + 6×0.25 + 15×(1/16) ≈ 3.4
hence 3 < a6 < 4
Answered by Thiyagarajan K | 29 Mar, 2019, 07:56: AM
Application Videos
-
Finding ratio of lengths of sides of a triangle when th ...
This explains how to find the angles of a triangle using the relation betwe... -
Distance of a point lying on the square and circle from ...
The question solved in this video uses the standard equation of a circle is... -
Area of triangle formed by tangent & normal to circ ...
The video explains how to find the area of a triangle formed by the tangent... -
Solving the DE using variable separation method
The video explains to find the solution of a differential equation using th... -
Solution of a Linear DE using Integrating factor
Question solved in the video explains to find the solution of linear differ...
Concept Videos
-
Properties of Inverse Trigonometry Part - 1
This video explains the properties of inverse trigonometric applications an... -
Trigonometric identities and problems
Fundamental trigonometric identities and problems based on them. Sign Conve... -
Graphical representation of inverse trigonometric funct ...
Graphical representation of inverse trigonometric functions and principle ... -
Degree measure and Radian measure ...
This video explains the concept of negative & positive angles, conversion o... -
Continuous and Discontinuous function
Understand the meaning of function to be continuous and discontinuous, comb...
JEE main - Maths
Asked by aniyoggavhane38 | 03 May, 2024, 09:41: PM
ANSWERED BY EXPERTJEE main - Maths
Asked by priyadharshinigopinath27 | 03 May, 2024, 08:44: PM
ANSWERED BY EXPERTJEE main - Maths
Asked by keerthananukala2007 | 02 May, 2024, 11:32: AM
ANSWERED BY EXPERTJEE main - Maths
Asked by amrutmasaguppi1108 | 01 May, 2024, 11:10: PM
ANSWERED BY EXPERTJEE main - Maths
Asked by ms9876tr | 28 Apr, 2024, 12:05: PM
ANSWERED BY EXPERTJEE main - Maths
Asked by jameelmohd765 | 27 Apr, 2024, 10:23: AM
ANSWERED BY EXPERT
