A, divide 2.5 by 5 and you get 0.5, multiply that by 9 and you get 4.5. A is the answer
Answer: -231 ft
<u>Step-by-step explanation:</u>
The submarine started at sea level = 0
It submerged 140 ft = -140 ft
It traveled 40 miles horizontally so it is still at -140 ft
It dove down an additional 120 ft = -260 ft <em>(-140 + -120)</em>
It traveled 25 miles horizontally so it is still at -260 ft
It rose 29 ft = -231 ft <em>(-260 + 29)</em>
Note: submerged and dove are negative values and rose is positive
0 - 140 - 120 + 29 = -231
Answer: see proof below
<u>Step-by-step explanation:</u>
Use the Double Angle Identity: sin 2Ф = 2sinФ · cosФ
Use the Sum/Difference Identities:
sin(α + β) = sinα · cosβ + cosα · sinβ
cos(α - β) = cosα · cosβ + sinα · sinβ
Use the Unit circle to evaluate: sin45 = cos45 = √2/2
Use the Double Angle Identities: sin2Ф = 2sinФ · cosФ
Use the Pythagorean Identity: cos²Ф + sin²Ф = 1
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<u>Proof LHS → RHS</u>
LHS: 2sin(45 + 2A) · cos(45 - 2A)
Sum/Difference: 2 (sin45·cos2A + cos45·sin2A) (cos45·cos2A + sin45·sin2A)
Unit Circle: 2[(√2/2)cos2A + (√2/2)sin2A][(√2/2)cos2A +(√2/2)·sin2A)]
Expand: 2[(1/2)cos²2A + cos2A·sin2A + (1/2)sin²2A]
Distribute: cos²2A + 2cos2A·sin2A + sin²2A
Pythagorean Identity: 1 + 2cos2A·sin2A
Double Angle: 1 + sin4A
LHS = RHS: 1 + sin4A = 1 + sin4A
Answer:0.25
Step-by-step explanation:
Just type it in a calculator