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Ask questions which are clear, concise and easy to understand.

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Because sine is p/h and if you will prepare a right triangle in second quadrant then only base will be in negative x otherwise both perpendicular and hypotenuse will be positive so sine and cosec are positive in second quadrant..
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Because only sine and cosine will positive on 2nd quadrantThanks (0)

Because all are positive in 2nd quadrantThanks (0)

Because at odd no of 90 x axis is changed by y axis and vice versa but at even no the axis is not changed just +Ive axis changed to negative and vice versa
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Physics is the branch of science which deals with the study of environment and natural phenomenon.Thanks (1)

Physics is the natural science that involves the study of matter and its motion and behavior through space and time, along with related concepts such as energy and force.
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what is urine

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Urine is a liquid byproduct of metabolism in the bodies of many animals, including humans. It is expelled from the kidneys and flows through the ureters to the urinary bladder, from which it is soon excreted from the body through the urethra during urination.
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The rotation of the earth having radius R about its axis speeds up to a value such that a man at latitude angle 60^{0} feels weightless. The duration of the day in such case will be?

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A spherical black body with a radius of 12cm radiates 440w power at 500K.If the radius were halved and the temperature doubled, the power radiated in watt would be

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Let original radius = r
Original temperature = T
Original power radiated = P
According to StefanBoltzmann Law, Power radiated by black body = {tex}P = σAT^4=\sigma 4\pi r^2T^4{/tex}
{tex}=> 500 = 4\sigma \pi r^2T^4{/tex}
New radius = {tex}r\over 2{/tex}
New temperature = 2T
New power P` = {tex}4\sigma \pi \times {r^2\over 4}\times 16T^4{/tex}
{tex}4\times (4\sigma \pi r^2T^4)= 4\times P{/tex}{tex}= 4\times 450= 1800{/tex}
Power becomes 1800 W
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more stable metal gold silver platinum

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A sample of 1.0g of solid Fe_{2}O_{3 }of 80%purity is dissolved in a moderately concentrated HCl solution which is reduced by zinc dust. The resulting solution required 16.7 mL of a 0.1M solution of the oxidant. Calculate the number of electrons taken up by the oxidant.

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What is the vector form of ohms law?

Current density,J=σE
where,σconductivity(scalar quantity) reciprocal of resistivity( ρ=R A/L)
EElectric field (vector quantity),E=Volt/Length
S.I unit of J (vector quantity)is Am^{2}.
Dimesionally ,
[J]=[σ][E]
or, A/m^{2}=(m/Ωm^{2}) (V/m)
Or,A= V/Ω
V=A*ohm(Ω ) So, J=sigm * electric field
Which vector form of ohm 's law:
V=I R
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(sinA+cosA)÷(sinAcosA)=x÷y, prove that xsquare +ysquare=2

The proof is possible when sinA+cosA=x and sinAcosA=y.
If division is there then proof is x²+y²=k²/2
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Sin…1\2√sinThanks (0)

x²+y²=(sinA+cosA) ² +(sinAcosA) ²
= 2
OR,
x+y=k sinA, xy=k cosA
x²+y²=1/2(k²sin²A + k²cos²A)
= 1/2 (k²(sin²A + cos²A))
= 1/2 *k²
= k²/2
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What is steady current?

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When the magnitude of the current does not vary with respect to time.Thanks (0)

A constant current is a type of Direct Current (DC) that does not change its intensity with time.
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Draw square root of 11on number line

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a projectile is projected from angle of prism at an angle alpha and it crosses the prism and reach exactly edge of the bottom.if alpha and beta are angle of prism then show that tan teta is equal to tan alpha plus tan beta

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If f^{1 }exist if f is
A) one to one function
B) surjective
C) bijective
D) into

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The answer is option A and B
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1. The maximum value of 10x5x^{2}1 is

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= 5 ( x^{2 } 2x)  1
= 5 (x^{2 } 2x + 1  1)  1
= 5 (x  1)^{2} + 5  1
= 4  5 (x  1)^{2}
Since ( x  1 )^{2} >= 0
5 (x  1)^{2} <= 0
4  5 (x  1)^{2} <= 4
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Hello . My doubt is that I want solution ( How to solve it , stepbystep) of the following Question : " if (Alpha)+(Beta)=3 and (Alpha)(Cube)+(Beta)(Cube)=7 , then (Alpha) and (Beta) are roots of equation "........................ .I hope that you would reply me soon .

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a+b=3 i. e. b=3a
a ³+b³=7 (Given)
(a+b) ³3ab(a+b)=7
Or, 279ab=7
Or, ab=20/9
Now, a(3a)=20/9
Or, 9a²27a+20=0
Solving by Sreedhar Achrya's formula,
We get,
a=5/3 or 4/3
and b=4/3 or 5/3
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