Answer:
The value of y is 6
units ⇒ 2nd answer
Step-by-step explanation:
In the attached figure
∵ ∠MTN is a right angle
∵ TU is the altitude of the triangle
- There are some rules in this triangle let us revise them
- (NT)² = NU . NM
- (MT)² = MU . MN
- (TU)² = MU . NU
- TM . TN = TU . MN
∵ NU = 9 units
∵ UM = 3 units
∵ MN = UM + NU
∴ MN = 3 + 9 = 12 units
- By using the 1st rule above
∴ (NT)² = 9 × 12
∴ (NT)² = 108
- Take a square root to both sides
∴ NT = 
- Simplify the root
∴ NT = 6 units
∵ NT is y
∴ y = 6 units
The value of y is 6 units
Write the left side of the given expression as N/D, where
N = sinA - sin3A + sin5A - sin7A
D = cosA - cos3A - cos5A + cos7A
Therefore we want to show that N/D = cot2A.
We shall use these identities:
sin x - sin y = 2cos((x+y)/2)*sin((x-y)/2)
cos x - cos y = -2sin((x+y)/2)*sin((x-y)2)
N = -(sin7A - sinA) + sin5A - sin3A
= -2cos4A*sin3A + 2cos4A*sinA
= 2cos4A(sinA - sin3A)
= 2cos4A*2cos(2A)sin(-A)
= -4cos4A*cos2A*sinA
D = cos7A + cosA - (cos5A + cos3A)
= 2cos4A*cos3A - 2cos4A*cosA
= 2cos4A(cos3A - cosA)
= 2cos4A*(-2)sin2A*sinA
= -4cos4A*sin2A*sinA
Therefore
N/D = [-4cos4A*cos2A*sinA]/[-4cos4A*sin2A*sinA]
= cos2A/sin2A
= cot2A
This verifies the identity.
Answer: -2
Step-by-step explanation:
The information in the question can be used to form an equation which goes thus:
2nd term = a + d = 4 ...... i
5th term = a + 4d = 22 ....... ii
From equation i
a = 4 - d ........ iii
Put equation iii into ii
a + 4d = 22
(4 - d) + 4d = 22
4 - d + 4d = 22
4 + 3d = 22
3d = 22 - 4
3d = 18
d = 18/3
d = 6
Commons difference is 6
Since a + d = 4
a + 6 = 4
a = 4 - 6
a = -2
The first term is -2
Answer:
Yes mark me brainliest
Step-by-step explanation:
We are given with
height = 9 feet
length = 10 feet
wall brackets:
48-in costing $12.95
60-in costing $16.95
distance of brackets from ends = 1 foot
maximum distance between brackets= 24 inches
The brackets are
48/12 = 4 feet
and
60/12 = 5 feet
One of each must be used to cover the height of the shelf
The length of the shelf is
60 inch
subtracting 1 in from each side for the allowance
60 - 2 = 58 in
Dividing by 24 inches
58/24 = 2.41 ~ 3
The total cost is
($12.95 + <span>$16.95) * 3 = $89.7
The total cost of the brackets is </span>$89.7
