Answer:
26.8°
Step-by-step explanation:
The cosine of an angle is the ratio of the adjacent side of the triangle in which the angle is formed to the hypotenuses side of the triangle. The cosine of the angle gives the ratio of these sides. However, the arc cosine of the ratio gives the angle measured in degrees.
If cos B = 0.8926
then arc cosine 0.8926 which may be expressed as cos-1 0.8926 will give the value of B.
B = cos-1 0.8926
= 26.8°
This one is so easy that your brain refuses to accept it.
It's looking for a harder answer, but can't find it !
You're totally correct, as far you went. x² + 2x does = -1
Now add ' 1 ' to each side: x² + 2x + 1 = 0
Can you factor that quadratic ?
Can you mash it through the quadratic formula ?
Actually, it's the simplest possible perfect square.
x² + 2x + 1 = (x + 1)²
So the solutions of x² + 2x + 1 = 0 are both x = -1 .
Don't say anything.
I know it's embarrassing.
Sequence 1,5,9,13,...
A(0) = 1 +4x0=1
A(1) =1 + 4x1 = 5
A(2) = 1+ 4x2= 9
A(3) = 1 +4x3=13
A(n)= 1+4n A(n-1) = 1+4(n-1) =1+4n-4= - 3+4n
A(n) - A(n-1) = (1+4n) - (-3=4n) = 4
A(n) = A(n-1) +4; 29 is the answer
Answer:
k = 63
Step-by-step explanation:
3 x 21 = 63