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Question Number 9187 Answers: 0 Comments: 0

Thanks!

Question Number 9172 Answers: 1 Comments: 1

The present age of a father and that of his son are in the ratio 7 : 1. After 4 years, the ratio will be 4 : 1. What is the son′s present age (in years) ?

$$\mathrm{The}\:\mathrm{present}\:\mathrm{age}\:\mathrm{of}\:\mathrm{a}\:\mathrm{father}\:\mathrm{and}\:\mathrm{that} \\ $$$$\mathrm{of}\:\mathrm{his}\:\mathrm{son}\:\mathrm{are}\:\mathrm{in}\:\mathrm{the}\:\mathrm{ratio}\:\mathrm{7}\::\:\mathrm{1}.\:\mathrm{After} \\ $$$$\mathrm{4}\:\mathrm{years},\:\mathrm{the}\:\mathrm{ratio}\:\mathrm{will}\:\mathrm{be}\:\mathrm{4}\::\:\mathrm{1}.\:\mathrm{What} \\ $$$$\mathrm{is}\:\mathrm{the}\:\mathrm{son}'\mathrm{s}\:\mathrm{present}\:\mathrm{age}\:\left(\mathrm{in}\:\mathrm{years}\right)\:? \\ $$

Question Number 9171 Answers: 1 Comments: 0

In a cricket team of 11, there 7 were atleast 20 years old and 8 were atmost 30 years old. The ages of how many were from 20 years to 30 years(both inclusive)?

$$\mathrm{In}\:\mathrm{a}\:\mathrm{cricket}\:\mathrm{team}\:\mathrm{of}\:\mathrm{11},\:\:\mathrm{there}\:\mathrm{7}\:\mathrm{were} \\ $$$$\mathrm{atleast}\:\mathrm{20}\:\mathrm{years}\:\mathrm{old}\:\mathrm{and}\:\mathrm{8}\:\mathrm{were}\:\mathrm{atmost} \\ $$$$\mathrm{30}\:\mathrm{years}\:\mathrm{old}.\:\mathrm{The}\:\mathrm{ages}\:\mathrm{of}\:\mathrm{how}\:\mathrm{many} \\ $$$$\mathrm{were}\:\mathrm{from}\:\mathrm{20}\:\mathrm{years}\:\mathrm{to}\:\mathrm{30}\:\mathrm{years}\left(\mathrm{both}\right. \\ $$$$\left.\mathrm{inclusive}\right)? \\ $$

Question Number 9168 Answers: 1 Comments: 0

If all the sides of a hexagon is increased by 2%. Find the % increase in its area.

$$\mathrm{If}\:\mathrm{all}\:\mathrm{the}\:\mathrm{sides}\:\mathrm{of}\:\mathrm{a}\:\mathrm{hexagon}\:\mathrm{is}\:\mathrm{increased} \\ $$$$\mathrm{by}\:\mathrm{2\%}.\:\mathrm{Find}\:\mathrm{the}\:\%\:\mathrm{increase}\:\mathrm{in}\:\mathrm{its}\:\mathrm{area}. \\ $$

Question Number 9167 Answers: 0 Comments: 4

A can do a work in 10 days and B can do the same work in 15 days. How many days will they take if both work together?

$$\mathrm{A}\:\mathrm{can}\:\mathrm{do}\:\mathrm{a}\:\mathrm{work}\:\mathrm{in}\:\mathrm{10}\:\mathrm{days}\:\mathrm{and}\:\mathrm{B}\:\mathrm{can} \\ $$$$\mathrm{do}\:\mathrm{the}\:\mathrm{same}\:\mathrm{work}\:\mathrm{in}\:\mathrm{15}\:\mathrm{days}.\:\mathrm{How}\: \\ $$$$\mathrm{many}\:\mathrm{days}\:\mathrm{will}\:\mathrm{they}\:\mathrm{take}\:\mathrm{if}\:\:\mathrm{both}\:\mathrm{work} \\ $$$$\mathrm{together}? \\ $$

Question Number 9166 Answers: 1 Comments: 1

x^(831) + y^(831) is always divisible by

$${x}^{\mathrm{831}} +\:{y}^{\mathrm{831}} \:\mathrm{is}\:\mathrm{always}\:\mathrm{divisible}\:\mathrm{by} \\ $$

Question Number 9165 Answers: 0 Comments: 0

x^(831) + y^(831) is always divisible by

$${x}^{\mathrm{831}} +\:{y}^{\mathrm{831}} \:\mathrm{is}\:\mathrm{always}\:\mathrm{divisible}\:\mathrm{by} \\ $$

Question Number 9163 Answers: 0 Comments: 2

show that the ellipse with e = ((√5)/3), focus (0, 2) and directrix x = −((4(√5))/3) has the equation : (((x − (√5))^2 )/9) + (((y − 2)^2 )/4) = 1

$$\mathrm{show}\:\mathrm{that}\:\mathrm{the}\:\mathrm{ellipse}\:\mathrm{with}\:\mathrm{e}\:=\:\frac{\sqrt{\mathrm{5}}}{\mathrm{3}},\: \\ $$$$\mathrm{focus}\:\left(\mathrm{0},\:\mathrm{2}\right)\:\mathrm{and}\:\mathrm{directrix}\:\mathrm{x}\:=\:−\frac{\mathrm{4}\sqrt{\mathrm{5}}}{\mathrm{3}} \\ $$$$\mathrm{has}\:\mathrm{the}\:\mathrm{equation}\::\:\frac{\left(\mathrm{x}\:−\:\sqrt{\mathrm{5}}\right)^{\mathrm{2}} }{\mathrm{9}}\:+\:\frac{\left(\mathrm{y}\:−\:\mathrm{2}\right)^{\mathrm{2}} }{\mathrm{4}}\:=\:\mathrm{1} \\ $$

Question Number 9161 Answers: 0 Comments: 2

Consider a rectangular plate of lamina density ρ = 0.025 whose mass is 5kg about an axis 3cm from one of its sides as shown below. using parallel axis theorem , find the moment of inertia about the xx axis and the radius of gyration.

$$\mathrm{Consider}\:\mathrm{a}\:\mathrm{rectangular}\:\mathrm{plate}\:\mathrm{of}\:\mathrm{lamina}\: \\ $$$$\mathrm{density}\:\rho\:=\:\mathrm{0}.\mathrm{025}\:\mathrm{whose}\:\mathrm{mass}\:\mathrm{is}\:\mathrm{5kg}\:\mathrm{about} \\ $$$$\mathrm{an}\:\mathrm{axis}\:\mathrm{3cm}\:\mathrm{from}\:\mathrm{one}\:\mathrm{of}\:\mathrm{its}\:\mathrm{sides}\:\mathrm{as}\:\mathrm{shown} \\ $$$$\mathrm{below}.\:\mathrm{using}\:\mathrm{parallel}\:\mathrm{axis}\:\mathrm{theorem}\:,\:\mathrm{find} \\ $$$$\mathrm{the}\:\mathrm{moment}\:\mathrm{of}\:\mathrm{inertia}\:\mathrm{about}\:\mathrm{the}\:\mathrm{xx}\:\mathrm{axis}\:\mathrm{and} \\ $$$$\mathrm{the}\:\mathrm{radius}\:\mathrm{of}\:\mathrm{gyration}. \\ $$

Question Number 9158 Answers: 1 Comments: 0

∫x^x dx = ?

$$\int{x}^{{x}} \:{dx}\:=\:? \\ $$

Question Number 9157 Answers: 1 Comments: 0

lim_(x→y) ((x^n − y^n )/(x − y))

$$\underset{{x}\rightarrow\mathrm{y}} {\mathrm{lim}}\:\:\frac{\mathrm{x}^{\mathrm{n}} \:−\:\mathrm{y}^{\mathrm{n}} }{\mathrm{x}\:−\:\mathrm{y}} \\ $$

Question Number 9149 Answers: 1 Comments: 0

1) bila seluruh energi potensial kembali menjadi kalor pada air terjun agar perbedaan suhu air diatas dan dibawah air terjun 1°C maka tinggi air terjun harus...?? 2) massa benda A 3 kali massa benda B dan kecepatan benda A setengah kali kecepatan B. Ek benda A dibandingkan Ek benda B adalah....?

$$\left.\mathrm{1}\right)\:\mathrm{bila}\:\mathrm{seluruh}\:\mathrm{energi}\:\mathrm{potensial}\:\mathrm{kembali} \\ $$$$\mathrm{menjadi}\:\mathrm{kalor}\:\mathrm{pada}\:\mathrm{air}\:\mathrm{terjun}\:\mathrm{agar} \\ $$$$\mathrm{perbedaan}\:\mathrm{suhu}\:\mathrm{air}\:\mathrm{diatas}\:\mathrm{dan}\:\mathrm{dibawah} \\ $$$$\mathrm{air}\:\mathrm{terjun}\:\mathrm{1}°\mathrm{C}\:\mathrm{maka}\:\mathrm{tinggi}\:\mathrm{air}\:\mathrm{terjun}\:\mathrm{harus}...?? \\ $$$$\left.\mathrm{2}\right)\:\mathrm{massa}\:\mathrm{benda}\:\mathrm{A}\:\mathrm{3}\:\mathrm{kali}\:\mathrm{massa}\:\mathrm{benda}\:\mathrm{B} \\ $$$$\mathrm{dan}\:\mathrm{kecepatan}\:\mathrm{benda}\:\mathrm{A}\:\mathrm{setengah}\:\mathrm{kali} \\ $$$$\mathrm{kecepatan}\:\mathrm{B}.\:\mathrm{Ek}\:\mathrm{benda}\:\mathrm{A}\:\mathrm{dibandingkan} \\ $$$$\mathrm{Ek}\:\mathrm{benda}\:\mathrm{B}\:\mathrm{adalah}....? \\ $$

Question Number 9141 Answers: 0 Comments: 5

Find the value of x if ((√(2 + (√3))))^x + ((√(2 − (√3))))^x = 4

$$\mathrm{Find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\mathrm{x}\:\mathrm{if} \\ $$$$\left(\sqrt{\mathrm{2}\:+\:\sqrt{\mathrm{3}}}\right)^{\mathrm{x}} \:+\:\left(\sqrt{\mathrm{2}\:−\:\sqrt{\mathrm{3}}}\right)^{\mathrm{x}} \:=\:\mathrm{4} \\ $$

Question Number 9144 Answers: 1 Comments: 0

Let f(x)=x^(2013) +2 (a).Find the remainder when f(x) is divided by x+1.(done) (b). Show that when 7^(2013) +2 is divided by 8, the remainder is 1. (please help!)

$${Let}\:{f}\left({x}\right)={x}^{\mathrm{2013}} +\mathrm{2} \\ $$$$\left({a}\right).{Find}\:{the}\:{remainder}\:{when}\:{f}\left({x}\right)\:{is}\:{divided}\:{by}\:{x}+\mathrm{1}.\left({done}\right) \\ $$$$\left({b}\right).\:{Show}\:{that}\:{when}\:\mathrm{7}^{\mathrm{2013}} +\mathrm{2}\:{is}\:{divided}\:{by}\:\mathrm{8},\:{the}\:{remainder} \\ $$$$\:\:\:\:\:\:\:\:\:\:{is}\:\mathrm{1}.\:\:\:\:\left({please}\:{help}!\right) \\ $$$$ \\ $$

Question Number 9128 Answers: 2 Comments: 1

Question Number 9125 Answers: 1 Comments: 0

A polygon has two interior angles of 120° each and the others are each 150°. calculate (a) The number of sides of the polygon . (b) The sum of the interior angles.

$$\mathrm{A}\:\mathrm{polygon}\:\mathrm{has}\:\mathrm{two}\:\mathrm{interior}\:\mathrm{angles}\:\mathrm{of}\:\mathrm{120}°\:\mathrm{each} \\ $$$$\mathrm{and}\:\mathrm{the}\:\mathrm{others}\:\mathrm{are}\:\mathrm{each}\:\mathrm{150}°.\:\mathrm{calculate} \\ $$$$\left(\mathrm{a}\right)\:\mathrm{The}\:\mathrm{number}\:\mathrm{of}\:\mathrm{sides}\:\mathrm{of}\:\mathrm{the}\:\mathrm{polygon}\:. \\ $$$$\left(\mathrm{b}\right)\:\mathrm{The}\:\mathrm{sum}\:\mathrm{of}\:\mathrm{the}\:\mathrm{interior}\:\mathrm{angles}. \\ $$

Question Number 9123 Answers: 0 Comments: 1

simplify (x^2 (x+1)^(−1/2) −(x+1)^(1/2) )/x^2

$$\mathrm{simplify} \\ $$$$\left(\mathrm{x}^{\mathrm{2}} \left(\mathrm{x}+\mathrm{1}\right)^{−\mathrm{1}/\mathrm{2}} −\left(\mathrm{x}+\mathrm{1}\right)^{\mathrm{1}/\mathrm{2}} \right)/\mathrm{x}^{\mathrm{2}} \\ $$

Question Number 9119 Answers: 1 Comments: 0

If x = 5^(1/4) + 5^(−1/4) and y = 5^(1/4) − 5^(−1/4) Show that : 5^((x^2 + y^2 )^2 ) = 144

$$\mathrm{If}\:\:\mathrm{x}\:=\:\mathrm{5}^{\mathrm{1}/\mathrm{4}} \:+\:\mathrm{5}^{−\mathrm{1}/\mathrm{4}} \:\:\:\mathrm{and}\:\:\mathrm{y}\:=\:\mathrm{5}^{\mathrm{1}/\mathrm{4}} \:−\:\mathrm{5}^{−\mathrm{1}/\mathrm{4}} \\ $$$$\mathrm{Show}\:\mathrm{that}\::\:\mathrm{5}^{\left(\mathrm{x}^{\mathrm{2}} \:+\:\mathrm{y}^{\mathrm{2}} \right)^{\mathrm{2}} \:} =\:\mathrm{144} \\ $$

Question Number 9113 Answers: 0 Comments: 1

∫_0 ^1 x^2 /x^2 +1=0

$$\int_{\mathrm{0}} ^{\mathrm{1}} \mathrm{x}^{\mathrm{2}} /\mathrm{x}^{\mathrm{2}} +\mathrm{1}=\mathrm{0} \\ $$

Question Number 9109 Answers: 1 Comments: 0

if y = x^(log_a xy) find (dy/dx)