If [latex]vec{a} . vec{c} =3 , vec{a} = hat{i}+ hat{j}+ hat{k}, vec{b} =hat{j} – hat{k}, vec{a} times vec{c} =vec{b}[/latex], Find [latex][vec{a} ; vec{b} ;; vec{c}][/latex] Solution:Answer: = -2... View Article
Solve [latex]lim_{n rightarrow infty} frac{1}{n}sum_{r=0}^{2n-1}frac{n^2}{n^2+4r^2}[/latex] Solution:Answer: [(1/2)] tan-14 - 0 = [(1/2)] tan-14 - 0... View Article
A wire of length 36 units is cut into two parts which are bent respectively to form a square of side x units and a circle of radius of r units. If the sum of areas of the square and the circle so formed is minimum, then find the circumference of the circle. Solution:Answer: 2π x 18/(4 + π) = 36π/(4 + π)Sum of perimeter of square and circle = 364x + 2πr = 36⇒2x + πr = 18x = (18... View Article
If [latex]arg(frac{z-1}{z+1}) = frac{pi}{4}[/latex], then find equation of circle. Solution:Answer: √2... View Article
Sum of infinite terms A, AR, AR2, AR3,…. is 15. If the sum of the square of these terms is 150, then find the sum of AR2, AR4, AR6, ⋯. Solution:Answer: ½ A + AR + AR2 + ⋯ = 15⇒A/(1-R) = 15 ⋯(i)Now, A2 + A2 R2 + A2 R4 + ⋯ = 150⇒A2/(1-R2 ) =... View Article
If cosx/(1+sinx) = |tanx|, then find the number of solutions in [0, 2π]. Solution:Answer: x = π/6Case 1: tan x ≥ 0cosx/(1+sinx ) = sinx/cosx⇒cos2x = sin2x+sinx⇒1-sin2x = sin2x + sinx⇒2 sin2x + sin... View Article
Evaluate [latex]int_{frac{-1}{sqrt{2}}}^{frac{1}{sqrt{2}}}[(frac{1-x}{1+x})^2 + (frac{1+x}{1-x})^2 – 2]dx[/latex] Solution:Answer: 4 ln ½... View Article
P(A) = p, P(B) = 2p, P(Exactly one out of A and B occurs) = 5/9. What will be the maximum value of p? Solution:Answer: 5/9 Given: P(A) = p and P(B) = 2p P(A)-P(A∩B)+P(B)-P(A∩B) = 5/93p-2P(A∩B) = 5/90 ≤ P(A∩B) ≤ pFor maximum... View Article
In a hospital, 89% has disease A and 98% has disease B, K% is the number of patients who has both, then K can’t be the subset of ____ Solution:Answer: Least k =87, Max k = 89Let total =100n(A)=89, n(B)=98max (n(A),n(B)) ≤ n(AUB) ≤ 10098 ≤ n(A)+n(B)-n(A n B) ≤... View Article
Find value of (5 – e2 ) for ellipse x2/8 + y2/4 = 1 Solution:Answer: 9/2x2/8 + y2/4 = 1a2 = 8, b2 = 4e = c/a = √((a2 - b2)/a2 ) = √(1-4/8) = √(1/2)(5 - e2 ) = 5 - 1/2 = 9/2... View Article
If loge (x+y) = 4xy. Find (d2y)/(dx2) at x = 0. Solution:Answer: 40loge (x+y) = 4xyor 1/((x + y)) [1 + (dy/dx)] = 4[x (dy/dx) + y]or 1 + (dy/dx) = 4(x + y) [x (dy/dx) + y]⋯(i)If x = 0, then y =... View Article
The sum of the square of the distance of a point from (0, 0), (0, 1), (1, 1), (1, 0) is 18 and its locus is a circle. If d is the diameter of the circle, then find d2 Solution:Answer: 16(OP) 2 + (AP) 2 + (PC) 2 + (PB) 2=18=> x2 + y2 + x2 + (y - 1) 2 + (x - 1) 2 + y2 + (x - 1) 2 + (y - 1) 2 =18=> 4x2 + 4y2... View Article
How many 3 digit numbers by using the digits 0,1,3,4,6,7 can be possible if repetition are allowed? Solution:Answer: 180digits 0,1,3,4,6So, 5 x 6x 6 = 180... View Article
f(x) = [latex]cos((2 tan^{-1}((sin((cot^{-1}(sqrt{((1-x)/x) )} ) )[/latex] then a. (1-x)2 f'(x) - 2(f(x)) 2 = 0b. (1-x) 2 f'(x) + 2(f(x)) 2= 0c. (1+x) 2 f'(x) - 2(f(x)) 2= 0d. (1+x) 2 f'(x)+2(f(x)) 2= 0Solution:Answer:... View Article
Which of the following is the correct sequence of the following conversion? a. Br2 / FeBr3, HNO3 / H2SO4, NaCN, H2O / H+b. HNO3 / H2SO4, Br2 / FeBr3, Mg / Ether, CO2, H3O+c. NaCN, H3O+, Br2 / FeBr3, H3O+ / CO2 / H2Od.... View Article
The ratio of water of crystallization present in Mohr’s salt to that of Potash alum is……..x 10-1? Solution:Answer: (2.5)Potash alum = K2(SO4).Al2(SO4)3.24H2OMohr’s salt = (NH4)2Fe(SO4)2.6H2ORatio of water molecule = = 0.25 = 2.5 x... View Article
In the given equation: + 2(â„Ž / = 125o ) → ? Solution:Answer: (a)Bromination is highly selective.Reactivity order is: 3o > 2o > 1o.... View Article
Choose the correct option for the given statements. Question: Choose the correct option for the given statements. Statement-I: Titration of a strong acid with a weak base uses methyl orange as an... View Article
Correct sequence of [Equation] of [Equation] at constant temperature. a. (At constant temperature)And as we know, Molar Mass: CO2 > O2 > N2Therefore, Urms : UN2 > UO2 > UCO2Hence, option a) is correct.... View Article