Answer:
At (-2,0) gradient is -4 ; At (2,0) gradient is 4
Step-by-step explanation:
For this problem, we simply need to take the derivative of the function and evaluate when y = 0 (when crossing the x-axis).
y = x^2 - 4
y' = 2x
The function y = x^2 - 4 cross the x-axis when:
y = x^2 - 4
0 = x^2 - 4
4 = x^2
2 +/- = x
Hence, this curve crosses the x-axis twice, once at (-2,0) and again at (2,0).
The gradient at these points are as follows:
y' = 2(-2) = -4
y' = 2(2) = 4
Cheers.
Answer:
A
Step-by-step explanation:
Those expressions are already in scientific notation.
The trick is to exploit the difference of squares formula,
Set a = √8 and b = √6, so that a + b is the expression in the denominator. Multiply by its conjugate a - b:
Whatever you do to the denominator, you have to do to the numerator too. So
Expand the numerator:
So we have
But √12 = √(3•4) = 2√3, so