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:
432 pages.
Step-by-step explanation:
We know Madison reads 24pgs/ per day. She reads for nine days, so she reads 24*9 pages, or 216.
We know also that this is halfway through her book, so 2*216= the whole book, so the book has 432 pages
Answer:
11.5 sec
Step-by-step explanation:5.5+6=11.5
Answer:10 hours to read all 250 pages
Step-by-step explanation: