Top answers

Maths
A Level

The number of bacteria present in a culture at time t hours is modeled by the continuous variable N and the relationship N = 2000e^kt, where k is a constant. Given that when t = 3, N = 18 000, find (a) the value of k to 3 significant figures

putting in the conditions: 18000 = 2000e^3k ..  ln(9) = 3k .. k=(1/3)ln(9)

BC
Answered by Benjamin C. Maths tutor
5105 Views

A circle has the equation x^2 + y^2 - 4x + 10y - 115 = 0. Express the equation in the form (x - a)^2 + (y - b)^2 = k, and find the centre and radius of the circle.

Rearrange the equation so that the x terms and y terms bracketed together, like so: (x^2 - 4x) + (y^2 + 10y) - 115 = 0. Complete the square on both sets of brackets, giving (x - 2)^2 - 4 + (y + 5)^2 - 25 ...

JB
Answered by Joseph B. Maths tutor
3724 Views

Find the indefinite integral of ( 32/(x^3) + bx) over x for some constant b.

To integrate (32/ x3 + bx) over x we can integrate each part separately. This is because addition of two integrals is the same as integrating the total of the elements. 

So we integrate ...

BO
Answered by Becky O. Maths tutor
3144 Views

Find the set of values of k for which x^2 + 2x+11 = k(2x-1)

The discriminant for a quadratic polynomial of the form f(x) = ax^2 + bx + c is given by b^2 - 4ac. If the discriminant is strictly greater than 2, the quadratic has 2 real distinct roots, i.e 2 unique x-...

WA
Answered by William A. Maths tutor
13737 Views

Parlami di cosa hai fatto durante le vacanze di Natale.

Le mie vacanze di Natale non sono state particolarmente emozionanti. Alla mia famiglia piace rispettare le tradizioni, quindi ho passato la vigilia coi miei nonni paterni e il giorno di natale con la nonn...

LV
Answered by Lorenzo V. Maths tutor
9549 Views

We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning