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Question Number 175010 Answers: 1 Comments: 1

A ball of p of mass 0.25kg losses (1/3) of its velocity when it makes an head on collision with an identical ball q at rest. After collision, q moves off with a velocity of 2ms^(−1) in the original direction of p. Calculate the initial velocity of p.

$$\:\mathrm{A}\:\mathrm{ball}\:\mathrm{of}\:\boldsymbol{\mathrm{p}}\:\mathrm{of}\:\mathrm{mass}\:\mathrm{0}.\mathrm{25kg}\:\mathrm{losses}\:\frac{\mathrm{1}}{\mathrm{3}}\:\mathrm{of}\: \\ $$$$\mathrm{its}\:\mathrm{velocity}\:\mathrm{when}\:\mathrm{it}\:\mathrm{makes}\:\mathrm{an}\:\mathrm{head}\:\mathrm{on} \\ $$$$\mathrm{collision}\:\mathrm{with}\:\mathrm{an}\:\mathrm{identical}\:\mathrm{ball}\:\boldsymbol{\mathrm{q}}\:\mathrm{at}\:\mathrm{rest}. \\ $$$$\mathrm{After}\:\mathrm{collision},\:\boldsymbol{\mathrm{q}}\:\mathrm{moves}\:\mathrm{off}\:\mathrm{with}\:\mathrm{a}\:\mathrm{velocity} \\ $$$$\mathrm{of}\:\mathrm{2ms}^{−\mathrm{1}} \:\mathrm{in}\:\mathrm{the}\:\mathrm{original}\:\mathrm{direction}\:\mathrm{of}\:\boldsymbol{\mathrm{p}}. \\ $$$$\mathrm{Calculate}\:\mathrm{the}\:\mathrm{initial}\:\mathrm{velocity}\:\mathrm{of}\:\boldsymbol{\mathrm{p}}. \\ $$

Question Number 174950 Answers: 1 Comments: 0

Have you seen this method of solving quadratic problem? x^2 −x−12=0 y′=±(√(b^2 −4ac))

$$\mathrm{Have}\:\mathrm{you}\:\mathrm{seen}\:\mathrm{this}\:\mathrm{method}\:\mathrm{of}\:\mathrm{solving} \\ $$$$\mathrm{quadratic}\:\mathrm{problem}? \\ $$$$\mathrm{x}^{\mathrm{2}} −\mathrm{x}−\mathrm{12}=\mathrm{0} \\ $$$$\mathrm{y}'=\pm\sqrt{\mathrm{b}^{\mathrm{2}} −\mathrm{4ac}} \\ $$

Question Number 174928 Answers: 3 Comments: 0

How many digits does 1000^(1000) have? Mastermind

$$\mathrm{How}\:\mathrm{many}\:\mathrm{digits}\:\mathrm{does}\:\mathrm{1000}^{\mathrm{1000}} \:\mathrm{have}? \\ $$$$ \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174853 Answers: 0 Comments: 2

By first principle, solve cos^2 x + sin^2 x=1

$$\mathrm{By}\:\mathrm{first}\:\mathrm{principle},\:\mathrm{solve}\:\mathrm{cos}^{\mathrm{2}} \mathrm{x}\:+\:\mathrm{sin}^{\mathrm{2}} \mathrm{x}=\mathrm{1} \\ $$

Question Number 174770 Answers: 1 Comments: 0

∫(((sinx)/( (√x))))dx Mastermind

$$\int\left(\frac{\mathrm{sinx}}{\:\sqrt{\mathrm{x}}}\right)\mathrm{dx} \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174742 Answers: 0 Comments: 0

≪_• ^• I THINK...^ ^(−) _•^• _(−) ≫ One question per post, IDEAL 👍👍👍 Two questions per post,OK (BEARABLE) (👎+👍)/2 Three or more questions:NO, NO, NO! 👎👎👎

Question Number 174661 Answers: 1 Comments: 0

After being marked down 20 percent. a calculator sells for $10. The Original selling price was ?

$$\mathrm{After}\:\mathrm{being}\:\mathrm{marked}\:\mathrm{down}\:\mathrm{20}\:\mathrm{percent}. \\ $$$$\mathrm{a}\:\mathrm{calculator}\:\mathrm{sells}\:\mathrm{for}\:\$\mathrm{10}.\:\mathrm{The}\:\mathrm{Original} \\ $$$$\mathrm{selling}\:\mathrm{price}\:\mathrm{was}\:? \\ $$

Question Number 174619 Answers: 2 Comments: 0

Question Number 174613 Answers: 1 Comments: 0

In a mixture of Skettles and M&M′s, 80% of the pieces are M&M′s. A fourth of this mixture is replaced by a second mixture, resulting in combination which contain 16% Skittles in total. What was the percentage of Skittles in the second mixture?

$$\mathrm{In}\:\mathrm{a}\:\mathrm{mixture}\:\mathrm{of}\:\:\mathrm{Skettles}\:\mathrm{and}\:\mathrm{M\&M}'\mathrm{s}, \\ $$$$\mathrm{80\%}\:\mathrm{of}\:\mathrm{the}\:\mathrm{pieces}\:\mathrm{are}\:\mathrm{M\&M}'\mathrm{s}.\:\mathrm{A}\:\mathrm{fourth} \\ $$$$\mathrm{of}\:\mathrm{this}\:\mathrm{mixture}\:\mathrm{is}\:\mathrm{replaced}\:\mathrm{by}\:\mathrm{a}\:\mathrm{second} \\ $$$$\mathrm{mixture},\:\mathrm{resulting}\:\mathrm{in}\:\mathrm{combination} \\ $$$$\mathrm{which}\:\mathrm{contain}\:\mathrm{16\%}\:\mathrm{Skittles}\:\mathrm{in}\:\mathrm{total}. \\ $$$$\mathrm{What}\:\mathrm{was}\:\mathrm{the}\:\mathrm{percentage}\:\mathrm{of}\:\mathrm{Skittles} \\ $$$$\mathrm{in}\:\mathrm{the}\:\mathrm{second}\:\mathrm{mixture}? \\ $$

Question Number 174612 Answers: 0 Comments: 1

Question Number 174594 Answers: 1 Comments: 0

Let σ(n) be the sum of all positive divisors of the integer n and let p be any prime number. show that σ(n)<2n holds true for all n of the form n=p^2 . Mastermind

$$\mathrm{Let}\:\sigma\left(\mathrm{n}\right)\:\mathrm{be}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{positive} \\ $$$$\mathrm{divisors}\:\mathrm{of}\:\mathrm{the}\:\mathrm{integer}\:\mathrm{n}\:\mathrm{and}\:\mathrm{let}\:\mathrm{p}\:\mathrm{be} \\ $$$$\mathrm{any}\:\mathrm{prime}\:\mathrm{number}.\:\mathrm{show}\:\mathrm{that}\: \\ $$$$\sigma\left(\mathrm{n}\right)<\mathrm{2n}\:\mathrm{holds}\:\mathrm{true}\:\mathrm{for}\:\mathrm{all}\:\mathrm{n}\:\mathrm{of}\:\mathrm{the}\: \\ $$$$\mathrm{form}\:\mathrm{n}=\mathrm{p}^{\mathrm{2}} . \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174591 Answers: 1 Comments: 0

The drawing below shows two equilateral triangles with side length a. The triangle are horizontally shifted by (a/2). Find the intersection area A of the two triangles (grey area).

$$\mathrm{The}\:\mathrm{drawing}\:\mathrm{below}\:\mathrm{shows}\:\mathrm{two}\: \\ $$$$\mathrm{equilateral}\:\mathrm{triangles}\:\mathrm{with}\:\mathrm{side}\:\mathrm{length} \\ $$$$\boldsymbol{\mathrm{a}}.\:\mathrm{The}\:\mathrm{triangle}\:\mathrm{are}\:\mathrm{horizontally}\:\mathrm{shifted} \\ $$$$\mathrm{by}\:\frac{\mathrm{a}}{\mathrm{2}}.\:\mathrm{Find}\:\mathrm{the}\:\mathrm{intersection}\:\mathrm{area}\:\mathrm{A}\:\mathrm{of} \\ $$$$\mathrm{the}\:\mathrm{two}\:\mathrm{triangles}\:\left(\mathrm{grey}\:\mathrm{area}\right). \\ $$$$ \\ $$$$ \\ $$$$ \\ $$

Question Number 174528 Answers: 1 Comments: 0

Question Number 174522 Answers: 0 Comments: 0

Let σ(n) be the sum of all positive divisors of the integer n and let p be any prime number. Show that σ(n)<2n holds true for all n of the form n=p^2 . Mastermind

$$\mathrm{Let}\:\sigma\left(\mathrm{n}\right)\:\mathrm{be}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{all}\:\mathrm{positive}\:\mathrm{divisors} \\ $$$$\mathrm{of}\:\mathrm{the}\:\mathrm{integer}\:\mathrm{n}\:\mathrm{and}\:\mathrm{let}\:\mathrm{p}\:\mathrm{be}\:\mathrm{any}\:\mathrm{prime} \\ $$$$\mathrm{number}.\:\mathrm{Show}\:\mathrm{that}\:\sigma\left(\mathrm{n}\right)<\mathrm{2n}\:\mathrm{holds}\:\mathrm{true} \\ $$$$\mathrm{for}\:\mathrm{all}\:\mathrm{n}\:\mathrm{of}\:\mathrm{the}\:\mathrm{form}\:\mathrm{n}=\mathrm{p}^{\mathrm{2}} . \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174507 Answers: 1 Comments: 0

Determine the numerical value of the following expression without the use of a calculator log[log(3)∙(log(2)∙((((√3)−2sin((π/3)))/(π^3 +1))+1))−log(2)log(3)+(−1)^(100) ] Mastermind

$$\mathrm{Determine}\:\mathrm{the}\:\mathrm{numerical}\:\mathrm{value}\:\mathrm{of}\:\mathrm{the}\: \\ $$$$\mathrm{following}\:\mathrm{expression}\:\mathrm{without}\:\mathrm{the}\:\mathrm{use} \\ $$$$\mathrm{of}\:\mathrm{a}\:\mathrm{calculator} \\ $$$$\mathrm{log}\left[\mathrm{log}\left(\mathrm{3}\right)\centerdot\left(\mathrm{log}\left(\mathrm{2}\right)\centerdot\left(\frac{\sqrt{\mathrm{3}}−\mathrm{2sin}\left(\frac{\pi}{\mathrm{3}}\right)}{\pi^{\mathrm{3}} +\mathrm{1}}+\mathrm{1}\right)\right)−\mathrm{log}\left(\mathrm{2}\right)\mathrm{log}\left(\mathrm{3}\right)+\left(−\mathrm{1}\right)^{\mathrm{100}} \right] \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174500 Answers: 1 Comments: 0

Find the values of the following infinite sum: 1+(3/π)+(3/π^2 )+(3/π^3 )+(3/π^4 )+(3/π^5 )+... Mastermind

$$\mathrm{Find}\:\mathrm{the}\:\mathrm{values}\:\mathrm{of}\:\mathrm{the}\:\mathrm{following}\:\mathrm{infinite} \\ $$$$\mathrm{sum}: \\ $$$$\mathrm{1}+\frac{\mathrm{3}}{\pi}+\frac{\mathrm{3}}{\pi^{\mathrm{2}} }+\frac{\mathrm{3}}{\pi^{\mathrm{3}} }+\frac{\mathrm{3}}{\pi^{\mathrm{4}} }+\frac{\mathrm{3}}{\pi^{\mathrm{5}} }+... \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174495 Answers: 2 Comments: 2

What are the roots of the function f(x)=(log(3^x )−2log(3))∙(x^2 −1) with x∈R? Mastermind

$$\mathrm{What}\:\mathrm{are}\:\mathrm{the}\:\mathrm{roots}\:\mathrm{of}\:\mathrm{the}\:\mathrm{function} \\ $$$$\mathrm{f}\left(\mathrm{x}\right)=\left(\mathrm{log}\left(\mathrm{3}^{\mathrm{x}} \right)−\mathrm{2log}\left(\mathrm{3}\right)\right)\centerdot\left(\mathrm{x}^{\mathrm{2}} −\mathrm{1}\right)\:\mathrm{with} \\ $$$$\mathrm{x}\in\mathrm{R}? \\ $$$$ \\ $$$$\mathrm{Mastermind} \\ $$

Question Number 174490 Answers: 0 Comments: 1

A die is rolled 57 times, what is the probability that the sum of its outcome is 100?

$$\mathrm{A}\:\mathrm{die}\:\mathrm{is}\:\mathrm{rolled}\:\mathrm{57}\:\mathrm{times},\:\mathrm{what}\:\mathrm{is}\:\mathrm{the} \\ $$$$\mathrm{probability}\:\mathrm{that}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{its}\:\mathrm{outcome} \\ $$$$\mathrm{is}\:\mathrm{100}? \\ $$

Question Number 174361 Answers: 0 Comments: 1