Top answers

Determine for what values of c, f(x)=4x^2-(2c+8)x+4 has no real roots.

For f(x) not to have any real roots, its discriminant, b 2 -4ac < 0. Plugging in the coefficients from f(x), this means (-(2c+8)) 2 -4x4x4 < 0.This means (-(2c+8)) 2 < 4x4x4So 4c 2 +32c+64 < 64 b...
AR
Answered by Alexander R. • Maths tutor
1578 Views

How do you work out the limiting reagent in a reaction?

The limiting reagent is the chemical substance that isn't in excess in the reaction compared to the other components. The way to calculate which reagent limits the reaction and how it progresses is to calcul...
FS
Answered by Fiona S. • Chemistry tutor
1836 Views

Show that the two vectors A= 2i+3j-k and B=3i-j+3k are perpendicular

We know that two vectors are perpendicular when their dot product is equal to 0. As you can see from the SQA Higher Maths formula sheet, the equation for the dot product is; A.B=a1b1+a2b2+a3b3. To answer thi...
SC
Answered by Samantha C. • Maths tutor
6951 Views

How do I evaluate the usefulness of a source?

When I look at a source, the technique I use to answer these types of questions is DAPAL, which stands for: Date - When was this written - was it written immediately after the event or years later? Author - ...
JR
Answered by Jo R. • History tutor
9077 Views

Why does time slow down for someone standing at the bottom of a mountain compared to time for someone at the top of a mountain?

The concept of time is influenced by the force of gravity. On a planet, gravity acts on every object within its gravitational field. The closer the object is to the surface of the planet, the greater influen...
AC
Answered by Albin C. • Physics tutor
3583 Views