Answer:
see explanation
Step-by-step explanation:
Using the double angle identity for sine
sin2x = 2sinxcosx
Consider left side
cos20°cos40°cos80°
= (2sin20°cos20°)cos40°cos80°
= (2sin40°cos40°)cos80°
= (sin80°cos80° )
= (2sin80°cos80° )
= . sin160°
= . sin(180 - 20)°
= . sin20°
= = right side , thus proven
Answer:
Percent of error of Logan's Estimate is 12.5%
Step-by-step explanation:
Given:
Actual Volume of sample =48 mL
Estimated Volume of sample = 42 mL
We need to find the percent errors of Logan estimate.
To calculate percent of error below are the steps.
Step 1: Subtract the Actual value from the estimated value.
Step 2: Take the absolute value of step 1
Step 3: Divide that answer by the Actual value.
Step 4: Multiply that answer by 100 and add the % symbol to express the answer as a percentage.
Now Substituting the values we get;
Step 1: To Subtract Actual Volume with Estimated Volume
Estimated Volume of sample - Actual Volume of sample = 42 - 48 = -6 mL
Step 2: Find Absolute value we get;
Step 3 : Divide that answer by the Actual volume.
Step 4: Multiply that answer by 100 and add the % symbol to express the answer as a percentage.
Hence Percent of error of Logan's Estimate is 12.5%
