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If sina40 ° is known to be a, then cos130 ° is equal to a
It is known that sin40 ° = A. if so, then
cos130=cos(90+40)=cos90*cos40-sin90*sin40= 0-sin40=-A
(sin50) ^ X - (tan50) ^ x is less than or equal to (sin50) ^ - Y - (tan50) ^ - y, find x + y =?
Because 0 < sin 50 ° 1, Tan 50 ° 1,
The function f (T) = (sin50 °) T - (tan50 °) t is a monotone decreasing function,
Based on the known inequality (sin50 °) x - (tan50 °) x ≤ (sin50 °) - Y - (tan50 °) - y, i.e. f (x) ≤ f (- y), the,
That is, x + y ≥ 0
What's 50 degrees?
I want fractions
0.766
There is no fractional expression
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