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Question Number 110939 Answers: 2 Comments: 1

Question Number 110926 Answers: 1 Comments: 0

A 2000kg car start from rest and accelerated to a final velocity of 20m/s in 16 seconds. Assuming a constant air resistance of 500N, find (i) the average power developed by the engine of the car. (ii) the instantaneous power developed by the engine when the car reaches its final speed.

$$\mathrm{A}\:\mathrm{2000kg}\:\mathrm{car}\:\mathrm{start}\:\mathrm{from}\:\mathrm{rest}\:\mathrm{and} \\ $$$$\mathrm{accelerated}\:\mathrm{to}\:\mathrm{a}\:\mathrm{final}\:\mathrm{velocity}\:\mathrm{of} \\ $$$$\mathrm{20m}/\mathrm{s}\:\mathrm{in}\:\mathrm{16}\:\mathrm{seconds}.\:\mathrm{Assuming}\:\mathrm{a} \\ $$$$\mathrm{constant}\:\mathrm{air}\:\mathrm{resistance}\:\mathrm{of}\:\mathrm{500N},\:\mathrm{find} \\ $$$$\left(\mathrm{i}\right)\:\mathrm{the}\:\mathrm{average}\:\mathrm{power}\:\mathrm{developed}\:\mathrm{by} \\ $$$$\mathrm{the}\:\mathrm{engine}\:\mathrm{of}\:\mathrm{the}\:\mathrm{car}. \\ $$$$\left(\mathrm{ii}\right)\:\mathrm{the}\:\mathrm{instantaneous}\:\mathrm{power} \\ $$$$\mathrm{developed}\:\mathrm{by}\:\mathrm{the}\:\mathrm{engine}\:\mathrm{when}\:\mathrm{the}\:\mathrm{car} \\ $$$$\mathrm{reaches}\:\mathrm{its}\:\mathrm{final}\:\mathrm{speed}. \\ $$

Question Number 110970 Answers: 2 Comments: 1

Question Number 110911 Answers: 0 Comments: 0

Four teachers A, B, C, and D each proposed two exercises, one on algebra and another on analyses, to form an exam. The students have to choose two exercises at random. 1. Calculate the probability P(a) of a student to choose two exercises on algebra. a\ P(a)=(3/(16)) , b\P(a)=(3/(14)) , c\P(a)=(1/4) , d\None 2. Calculate the probability P(b) of choosing two exercises proposed by the same teacher. a\P(b)=(1/(10)) , b\P(b)=(1/(60)) , c\P(b)=(1/7) , d\None 3. Calculate the probability P(c) of choosing two exercises proposed by teacher A. a\P(c)=(1/3) , b\P(c)=(1/4) , c\P(c)=(1/(28)) , d\None

Question Number 110910 Answers: 2 Comments: 0

mr M.N july 1970 the question you posted earlier here goes the solution ∫_0 ^(1/2) ((ln^2 (1−x))/x)dx

$${mr}\:{M}.{N}\:{july}\:\mathrm{1970}\:{the}\:{question}\:{you}\:{posted}\:{earlier}\:{here}\:{goes}\:{the}\:{solution} \\ $$$$\int_{\mathrm{0}} ^{\frac{\mathrm{1}}{\mathrm{2}}} \frac{\mathrm{ln}^{\mathrm{2}} \left(\mathrm{1}−{x}\right)}{{x}}{dx} \\ $$$$ \\ $$

Question Number 110897 Answers: 3 Comments: 0

(1)4x−4 ≤ ∣x^2 −3x+2 ∣ find the solution set (2) ((1+cos ((α/2))−sin ((α/2)))/(1−cos ((α/2))−sin ((α/2))))=?

$$\left(\mathrm{1}\right)\mathrm{4x}−\mathrm{4}\:\leqslant\:\mid\mathrm{x}^{\mathrm{2}} −\mathrm{3x}+\mathrm{2}\:\mid\: \\ $$$$\mathrm{find}\:\mathrm{the}\:\mathrm{solution}\:\mathrm{set}\: \\ $$$$\left(\mathrm{2}\right)\:\frac{\mathrm{1}+\mathrm{cos}\:\left(\frac{\alpha}{\mathrm{2}}\right)−\mathrm{sin}\:\left(\frac{\alpha}{\mathrm{2}}\right)}{\mathrm{1}−\mathrm{cos}\:\left(\frac{\alpha}{\mathrm{2}}\right)−\mathrm{sin}\:\left(\frac{\alpha}{\mathrm{2}}\right)}=? \\ $$

Question Number 110895 Answers: 3 Comments: 0

How many ways can 2018 be expressed as the sum of two squares?

$$\mathrm{How}\:\mathrm{many}\:\mathrm{ways}\:\mathrm{can}\:\mathrm{2018}\:\mathrm{be} \\ $$$$\mathrm{expressed}\:\mathrm{as}\:\mathrm{the}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{two}\:\mathrm{squares}? \\ $$

Question Number 110879 Answers: 0 Comments: 1

Question Number 110875 Answers: 4 Comments: 0

(1)∫_e ^e^e ((ln (x).ln (ln (x)))/x) dx ? (2)lim_(x→π/4) ((cosec^2 x−2)/(cot x−1)) (3) Given { ((xy=((16y−9x)/(45)))),(((4/( (√x)))−(3/( (√y))) = 5)) :} ⇒find 9(√(xy))

$$\left(\mathrm{1}\right)\underset{\mathrm{e}} {\overset{\mathrm{e}^{\mathrm{e}} } {\int}}\:\frac{\mathrm{ln}\:\left(\mathrm{x}\right).\mathrm{ln}\:\left(\mathrm{ln}\:\left(\mathrm{x}\right)\right)}{\mathrm{x}}\:\mathrm{dx}\:? \\ $$$$\left(\mathrm{2}\right)\underset{{x}\rightarrow\pi/\mathrm{4}} {\mathrm{lim}}\:\frac{\mathrm{cosec}\:^{\mathrm{2}} \mathrm{x}−\mathrm{2}}{\mathrm{cot}\:\mathrm{x}−\mathrm{1}} \\ $$$$\left(\mathrm{3}\right)\:\mathrm{Given}\:\begin{cases}{\mathrm{xy}=\frac{\mathrm{16y}−\mathrm{9x}}{\mathrm{45}}}\\{\frac{\mathrm{4}}{\:\sqrt{\mathrm{x}}}−\frac{\mathrm{3}}{\:\sqrt{\mathrm{y}}}\:=\:\mathrm{5}}\end{cases} \\ $$$$\Rightarrow\mathrm{find}\:\mathrm{9}\sqrt{\mathrm{xy}} \\ $$

Question Number 110869 Answers: 1 Comments: 0