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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 lot easier. In fact, given the equat...
CG
6275 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 we c...
PG
Answered by Pierce G. • Maths tutor
4569 Views

State the trigonometric identities for sin2x, cos2x and tan2x

sin2x = 2sinxcosx cos2x = cos^2(x) - sin^2(x) tan2x = (2tanx)/(1-tan^2(x))
JS
Answered by James S. • Maths tutor
21077 Views

Find the coordinates of the point of intersection of the lines y = 5x - 2 and x + 3y = 8.

substitute y=5x-2 into second equation --> x + 3(5x- 2)= 8// 2) factorise and simplify to get 16x=14 3) divide 14 by 16 to calculate the value of x to be 7/8 4) sub value of x into equation 1 to find the...
AT
Answered by Anand T. • Maths tutor
6410 Views

Find dy/dx of the equation y=x^2 ln⁡(2x^2+1).

This question requires the use of two key rules of differentiating. The first of these is the product rule. The product rule describes a way of differentiating an equation which is the product of two differe...
CL
Answered by Cameron L. • Maths tutor
5237 Views