Doubtly
@Doubtly · Joined Feb 2021
- Answers
- 3,792
- Questions
- 4,033
- Upvotes received
- 424
- The mean of 6 numbers is 6.5 and its variance is 10.25. If 4 numbers are 2,4,5 and 7, then find the other two. Answer: the other two numbers are 10 and 11 Let the other two numbers be a and b . Mean: sum of all six = 6×6.5 = 39 . The given four add to... 1
- The initial velocity vi required to project a body vertically upward from the surface of the earth to reach a height of 10R, where R is the radius of the earth, Correct answer is 10 1
- The radius in kilometer to which the present radius of earth (R = 6400 km) Correct answer is 64 km Explanation:: 1
- which of the following is most easily economically refined by fractional distillation Correct option is A) Zn 2
- If P4O10 + HNO3 are mixed in 1:4 ratio , then nature of nitrogen oxide obtained will be 4HNO₃ +P₄ O₁₀ →2N₂ O ₅+4HPO_(3 ) and N₂O₅ is acidic in nature 1
- What is disproportionate ? in chemistry A disproportionation reaction is one in which a species has been both oxidised and reduced (that is, the oxidation state of the related spec... 1
- Benzene has vapor pressure of 70 torr and methyl benzene has 20 torr . Answer: y_benzene = 7/9 ≈ 0.78 For an equimolar ideal solution, x_benzene = x_toluene = 0.5 . By Raoult's law, the partial pressures are p_B... 1
- In △ABC , cos B= 3/5 , AB=5 and R=5 . find the area of △ABC correct answer is 6+8√3 2
- find the coefficient of x^256 in [1-x]^101 x (x^2+x+1)^100 Correct answer is ¹⁰⁰C₈₅ or ¹⁰⁰C₁₅ 1
- tangent and normal are drawn to y^2=2x at A(2,2). tangent cuts x-axix at T and normal cuts parabola again at P Ans is : 25/2 {area of ▵ ATP } 2
- Bird is flying in northeast direction with v 4rt^2 wind from north to south with 1m/s find the Ans: 15 m {displacement of bird} 2
- If both FeX2 & FeY3 are found to exist, X & Y can be : (1) X = F, Cl, Br, I Y = F, Cl, Br (2) X = Cl, Br, (1) X = F, Cl, Br, I :: Y = F, Cl, Br is the correct option Explaination:: FeI₃ does not exist as I^(–) reduces Fe³⁺ to Fe²⁺. 2Fe³⁺ + 2I – →... 1
- The period of oscillation of a simple pendulum is T = 2π\sqrt{Lg}. Measured value of 'L' is 1.0 m from meter Answer: (1) 1.13% Step 1: Write g in terms of the measured quantities. T = 2π√(L/g) ⇒ g = frac4π²LT² Step 2: Relative error. For a product o... 1
- WAP in C++ that first initializes an array of given 10- sorted real numbers. The program must verify whether a given Output:: Below code is executed on gdb turbo c++ compiler , it takes 10 input of given number then sort by binary search technique #include<... 2
- write html code for following Faculty Arts Science Commerce Code :: <!DOCTYPE html> <table border="1" cellspacing="10px"> <tr> <th rowspan="2" colspan="2" > </th> <th colspan="3"> Faculty</th> </tr> <... 1
- The least value of |z| where z is complex number which satisfies the inequality Answer: (1) 3 Read the inequality as exp((|z|+3)(|z|-1)/|z|+1log_e 2) ≥ log_(sqrt2)|5sqrt7 + 9i| . Right side: |5sqrt7 + 9i| = √(175 + 81) =... 1
- The area of the triangle with vertices A(z), B(iz) and C (z + iz) is : Answer: (2) 1/2|z|² Look at the sides meeting at C: overrightarrowCA = z - (z + iz) = -iz , length |z| . overrightarrowCB = iz - (z + iz) =... 1
- Let S1, S2 and S3 be three sets defined as S1 = {z ∈ C : |z - 1| ≤ √2} Answer: (3) Has infinitely many elements Let z = x + iy . S₁ : |z-1| ≤ sqrt2 is the closed disc with centre (1, 0) and radius sqrt2 . S₂ : (... 1