You have to find first the discriminant
∆=8^2-4*(-1) *(-7) =36
x=(-8±√36) /-2=(-8±6)/-2=4±3=1 or 7
So x(1)=1 or x(2)=7
-x^2+8x-7=[x-x(1) ][x-x(2) ]=(x-1) (x-7)
Let a =107° and b=42°;
So cos 107° cos 42° + sin 107° sin 42° = cosa.cos42 + sina.sinb = cos(a-b)
and cos 107° cos 42° + sin 107° sin 42° = cos(107-42) = cos(65°)
A normally distributed result means that when the data is
plotted on a graph, we can actually see a bell shaped curve. That highest
frequency or peak is centered on the average value. Because it is shaped like
this, we can say that:
most scores are around the average with some scores being
lower or higher
We'll use PEMDAS which stands for
P = parenthesis
E = exponents
M = multiplication
D = division
A = addition
S = subtraction
It tells us the order in how to evaluate math expressions. We start with parenthesis, then move to exponents, etc until we get to subtraction as the last step.
We have parenthesis so we focus on whats inside it. We evaluate 2^0 to get 1. Any nonzero number to the exponent 0 is always 1. In other words, x^0 = 1 where x is nonzero.
So 3(2^0) turns into 3(1) or 3*1
Then we multiply that to get 3*1 = 3
So overall, 3(2^0) = 3
Always congruent due to the way the shape is built
