Top answers

Starting with x^2+2x+1=0 use the method of factorising to solve for x.

x 2 +2x+1=0, (x+1)(x+1)=0, (x+1) 2 =0. So x=-1
RD
Answered by Rebecca D. • Maths tutor
4536 Views

How do I make sure I know all my vocab?

I recommend using study cards. Write down the spanish word on one side and the english word on the other side. Set yourself the task of learning 5 words a day and ask someone to test you.
EC
Answered by Ellie C. • Spanish tutor
2356 Views

Aluminium is protected from rust by a layer of oxidised Al2O3. Can you write a balanced equation for the formation of this layer?

To form Al2O3 you need both Al and O2 (oxygen gas is a dimer): Al + O2 -> Al2O3 But this equation is not balanced. To balance it, first equate the number of oxygen atoms: Al + 3O2 -> 2Al2O3 Now you hav...
JB
Answered by Jessica B. • Chemistry tutor
3652 Views

How do I say I don't like maths because its difficult?

No me gustan las matemáticas porque son difíciles.
IS
Answered by Itxaso S. • Spanish tutor
4047 Views

Consider f:R -> R, f = x/ sqrt(x^2+1). Prove that for any a between -1 and 1, f(x)=a has only one solution.

f'(x)=( sqrt (x^2+1) - x * ( x / sqrt (x^2 +1) ) ) / (x^2+1) = (x^2 + 1 + x^2) / ( (x^2 + 1) * sqrt ( x^2 + 1) ) = 1 / ( (x^2 + 1) * sqrt (x^2 + 1) ). f'(x) > 0 for any x => f is increasing. When x-&gt...
AC
3646 Views