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Since sin = root number 2cos, so sin 2 = 2cos 2, then cos 2 = 1-2cos 2
Because tan = root number 3cot
So tan 2 = 3 cot 2 = 3 cos 2 sin 2 = 3 cos 2 (1-cos 2).
And because tan 2=sin 2 cos 2 = 2cos 2 (1-2cos 2).
So 3cos2 (1-cos2) = 2cos2 (1-2cos2).
If cos = 0, then sin = 0, but , belong to (0, pie), so there is no solution at this time.
When cos is not 0, there will be 3-6cos 2=2-2cos 2
cosβ^2=1/4
cos = 1 2 or -1 2
But cos = -1 2.
sin = - root number 2 2<0, can belong to (0, pie), sin >0
So cos is not -1 2
cos can only be 1 2
60 degrees. Because tan = root number 3cot = 1, and belongs to (0, pie).
So =45 degrees.
In summary, =45 degrees, =60 degrees.
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Because sin = root number 2< = 1
So cos <=1 2
Because tan = root number 3cot, therefore, belongs to (0, 1 2 * pie], so tan = root number [sin 2 (1-sin 2)], i.e. 3cot = 2cos (1-2cos) so 3cos sin = 2cos (1-2cos), i.e. cos = 0 or 2sin = 3 (1-2cos) The solution is = 90 degrees or =arccos(9 + root number 31 20) (> 1 2, round).
or =arccos[(9-root, number, 31) 20], so =0 degrees(round), or =arcsinroot[(9-root, number, 31) 10], in summary, =arcsinroot[(9-root: number: 31) 10], =arccos[(9-root: number: 31) 20].
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Because sin = 2cos
So sin cos = 2, sin = 2cos because tan = 3ctg
Because sin = 2cos
So (sin) 2=2(cos) 2
Because cos = sin 6 3
So (cos) 2=2 3(sin) 2 add up: 2(cos) 2 2 3(sin) 2 16(cos) 2 2(sin) 2 34(cos) 2 1
cos = 1 2 or cos = -1 2cos =1 2, sin = 3 2, ctg = 3 3 then sin = 2 2, tan =1
cos = -1 2, sin = 3 2, ctg =- 3 3 then sin =- 2 2, tan =-1 in the fourth quadrant, rounded.
In summary, =45, =60
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First of all, the first argument potato examines a formula sina+cosa = root number 2 and eggplant 3 about the same time squared, to get 1 + 2sinac0sa=2 3, near and hand excitation sinacosa = minus 1 6, sina-c0sa squared to get 1-2 sinacosa into the number of dramas The above formula is 4 3, and because a (0, 丌) is from the original formula 2 3 3 or -2 3 3
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Both sides of the square have (sina) 2+6sinacosa+9(cosa) 2=10=10(sina) 2+10(cosa) 2, and the two tribes are cautious and divide by (cosa) 2.
tana) 2+6tana+9=10(tana) 2+10, solve tana=1 filial piety code 3
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The square of both sides (sin -cos) = 2
That is, sin -2 sin cos +cos = 2 and sin +cos = 1
So -2sin cos = 1
i.e. sin2 = -1
and (0, )
So 2 (0,2).
Therefore 2 = 3 2
So =3 4
then tan = tan (3 4) = -1
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sin -cos = root number 2 both sides squared at the same time yield: sina 2 + cosa 2-2sin *cos =2 i.e.: 1-sin2a=2 The answer is -1
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sin -cos = root number 2 both sides squared at the same time yield: sina 2 + cosa 2-2sin *cos =2 i.e.: 1-sin2a=2 The answer is -1
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Solution sina-cosa = 2
Both sides are squared:
sina-cosa)²=2
i.e., sin a-2sinacosa+cos a=2, i.e., 1-2sinacosa=2
2sinacosa=-1
sin2a=2sinacosa=-1
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sin = 2cos, formula; tan = sin cos = 3cot = 3cos sin, two formulas;
1 2 2 formula: cos = 6sin 3, three formulas;
Combining one formula and three formulas obtains: sin +cos = ( 2cos ) 6sin 3) =2cos +2sin 3
2(cos²β+sin²β)4sin²β/3=2-4sin²β/3=1;4sin²β/3=1,sinβ=√3/2,cosβ=1/2;
sinβ=√2/2
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From sin = root number 2cos, tan = root number 3cot can be known as cos = 2 3
Because 0< 0
So sin = 5 9
It can be seen that cos = 5 18
0< 0 again
So sin = 13 18
Answer:- 6 b 4
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