Top answers


Sketch the curve y = x^2 - 6x + 5, identifying roots and minima/maxima.

Remeber the formula: (a - b) 2 = a 2 - 2ab + b 2 . Notice that y = x 2 - 2 3 x + 5, so we want to write this using (x - 3 ) 2 = x 2 - 2 3 x* + 9. Taking 4 from both sides gives: (x - 3) 2 - 4 = x 2 - 6x + 5 ...
TD
Answered by Tutor69809 D. Maths tutor
6168 Views

a) Let u=(2,3,-1) and w=(3,-1,p). Given that u is perpendicular to w, find the value of p. b)Let v=(1,q,5). Given that modulus v = sqrt(42), find the possible values of q.

a) u is perpendicular to w , so u • w =0. This means that 2 3 + 3 (-1) + (-1)*p = 0, so 6-3-p=0, hence p=3. b) The magnitude of v = sqrt(1 2 +q 2 +5 2 ) = sqrt(42). Thus, 1+q 2 +25 = 42, q 2 =16, so q is eit...
CR
Answered by Cristiana R. Maths tutor
4369 Views

Solve for x 2x +3 + (4x-1)/2 = 10

2x +3 + (4x-1)/2 = 10 The divisor (2) is the biggest problem right now so we need to get it on its own... (4x-1)/2 = 10-2x-3 Equation has been rearranged! 4x-1 = 2(10-2x-3) Now we can eliminate the divisor b...
SH
Answered by Shannon H. Maths tutor
5832 Views

Use the substitution u=3+(x+4)^1/2 to find the integral of 1/(3+(x+4)^1/2) dx between 0 and 5.

We will call the integral I, so I = integral of 1/(3+(x+4) 1/2 ) dx between 0 and 5. First substitute u=3+(x+4) 1/2 into the equation to get I = integral of 1/u dx between 0 and 5 Next we want to change the ...
CB
Answered by Calum B. Maths tutor
4330 Views

Find the centre and radius of the circle with equation: x^2 + y^2 -4x +8y = 5, and determine whether the point (7,-4) lies on the circle.

First we complete the square on the equation of the circle to obtain: (x-2)^2 -4 + (y+4)^2 -16 = 5. Re arrange : (x-2)^2 + (y+4)^2 = 25 General equation of a circle: (x-a)^2 + (y-b)^2 = r^2, with centre (a,b...
AS
Answered by Alec S. Maths tutor
6674 Views