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If a-b=3,ab=7,then(a+b)is _______

D,E,F are the midpoints of a triangle ABC then what is the area of triangle DEF?

A farmer buys a land.There were lots of insectivorous plants in it.He was unaware of this,but when he came to know this he decided not to cultivate any crops and return the land.What could be the reason behind this decision?

what is the need for vertebrates to evolve from oviparity to viviparity?

1.The potiential energy of a particle varies with distance x from a fixed origin as v=A√x/x+B where A and B are constants.Find the dimensions of AB. 2.The refractive index of a material is given by the equation ʯ=A+B/ʎsquare where A and B are constants,ʎ...

The length and breadth of a rectangular sheet are 16.2 cm and 10.1cm, respectively. The area of the sheet in appropriate significant figures and error is (a) 164 ± 3 cm2 (b) 163.62 ± 2.6 cm2 (c) 163.6 ± 2.6 cm2 (d) 163.62 ± 3 cm2 please explain me what is...

Is g = {(1, 1), (2, 3), (3, 5), (4, 7)} a function? Justify. If this is described by the relation, g (x) = αx + β, then what values should be assigned to α and β?

A car accelerates from rest at a constant rate A for some time after which it retards at a constant rate B to come to rest. If the time elapsed is T second,calculate the maximum velocity reached?(please try solving this problem by plotting velocity time g...

show that cos2x=1-tan^ 2 x /1+tan^2x=2cos^2x-1

1.In one dimensional motion, instantaneous speed v satisfies 0 ≤ v < v0. (a) The displacement in time T must always take non-negative values. (b) The displacement x in time T satisfies – vo T < x < vo T. (c) The acceleration is always a non-negative numbe...