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The quadratic equation 2x^2+ 6x+7 has roots a and b. Write down the value of a+b and the value of ab.

A general method would be to compute a and b with the general solution formula for quadratic equations. However, a special property of quadratic equations can make this a...

Answered by Cesare Giulio A. • Maths tutor

5680 Views

Define hard engineering in the context of coastal managment

Hard engineering is a method of coastal management that involves the building of large and generally expensive features in order to defend against the sea,this usually includes building sea walls, groynes...

Answered by Laurence W. • Geography tutor

4830 Views

state the difference between a normal and a reverse fault

A normal fault is a fault that involves extensional movement along its fault plane, this involves the hanging wall moving down in relation to the footwall. A reverse fault involves contraction along its f...

Answered by Laurence W. • Geology tutor

9061 Views

In a titration, 50 cm3 of sodium hydroxide with a concentration of 0.3 mol/dm3 was neutralised by 60 cm3 of hydrochloric acid. Calculate the concentration of the hydrochloric acid in mol/dm3.

HCl + NaOH = NaCl + H2O. Moles = volume (dm3) x concentration (mol/dm3). Moles of NaOH: volume x concentration = (50/1000) x 0.3 = 0.015 moles. 1 to 1 ratio of HCl to NaOH, so there were 0.015 moles of HC...

Answered by Aarushi V. • Chemistry tutor

25737 Views

find dy/dx of the equation y=ln(x)2x^2

Here it is necessary to use the chain rule to solve the derivative. If we equate our equation in terms of the following notation: ln(x)='u'and 2x^2='v' and use the chain rule formula dy/dx=udv/dx+vdu/dx w...

Answered by Pierce G. • Maths tutor

4024 Views