1/cos80º-根号3/sin80º=?
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![1/cos80º-根号3/sin80º=?](/uploads/image/z/3722203-19-3.jpg?t=1%2Fcos80%26%23186%3B-%E6%A0%B9%E5%8F%B73%2Fsin80%26%23186%3B%3D%3F)
1/cos80º-根号3/sin80º=?
1/cos80º-根号3/sin80º=?
1/cos80º-根号3/sin80º=?
1/cos80-根号3/sin80
=1/sin10°-(根号3)/cos10°
=(cos10°-(根号3)sin10°)/(sin10°×cos10°)
=2(1/2 cos10°- (根号3)/2 sin10°))/(sin10°×cos10°
=2(sin30°cos10°-cos30°sin10°)/(sin10°×cos10°)
=2sin20°/(sin10°×cos10°)
=4sin20°/(2sin10°×cos10°)
=4sin20°/sin20°
=4
1/cos80º-√3/sin80º
= [sin80º-√3cos80º]/[sin80ºcos80º]
= 2[sin(80º-60º)]/ [(1/2)sin160º]
=4sin20º/sin160º
= 4sin20º/sin20º
=4