解
49.55⋅1−sin2(θ)−30sin(θ)=1.225
解
θ=1.00522…+2πn,θ=π−1.00522…+2πn
+1
度
θ=57.59542…∘+360∘n,θ=122.40457…∘+360∘n解答ステップ
49.551−sin2(θ)−30sin(θ)=1.225
置換で解く
49.551−sin2(θ)−30sin(θ)=1.225
仮定:sin(θ)=u49.551−u2−30u=1.225
49.551−u2−30u=1.225:u=2−0.02190…+2.92573…
49.551−u2−30u=1.225
平方根を削除する
49.551−u2−30u=1.225
両辺に30uを足す49.551−u2−30u+30u=1.225+30u
簡素化49.551−u2=1.225+30u
両辺を2乗する:2455.2025−2455.2025u2=1.500625+73.5u+900u2
49.551−u2−30u=1.225
(49.551−u2)2=(1.225+30u)2
拡張 (49.551−u2)2:2455.2025−2455.2025u2
(49.551−u2)2
指数の規則を適用する: (a⋅b)n=anbn=49.552(1−u2)2
(1−u2)2:1−u2
累乗根の規則を適用する: a=a21=((1−u2)21)2
指数の規則を適用する: (ab)c=abc=(1−u2)21⋅2
21⋅2=1
21⋅2
分数を乗じる: a⋅cb=ca⋅b=21⋅2
共通因数を約分する:2=1
=1−u2
=49.552(1−u2)
49.552=2455.2025=2455.2025(1−u2)
拡張 2455.2025(1−u2):2455.2025−2455.2025u2
2455.2025(1−u2)
分配法則を適用する: a(b−c)=ab−aca=2455.2025,b=1,c=u2=2455.2025⋅1−2455.2025u2
=1⋅2455.2025−2455.2025u2
数を乗じる:1⋅2455.2025=2455.2025=2455.2025−2455.2025u2
=2455.2025−2455.2025u2
拡張 (1.225+30u)2:1.500625+73.5u+900u2
(1.225+30u)2
完全平方式を適用する: (a+b)2=a2+2ab+b2a=1.225,b=30u
=1.2252+2⋅1.225⋅30u+(30u)2
簡素化 1.2252+2⋅1.225⋅30u+(30u)2:1.500625+73.5u+900u2
1.2252+2⋅1.225⋅30u+(30u)2
1.2252=1.500625
1.2252
1.2252=1.500625=1.500625
2⋅1.225⋅30u=73.5u
2⋅1.225⋅30u
数を乗じる:2⋅1.225⋅30=73.5=73.5u
(30u)2=900u2
(30u)2
指数の規則を適用する: (a⋅b)n=anbn=302u2
302=900=900u2
=1.500625+73.5u+900u2
=1.500625+73.5u+900u2
2455.2025−2455.2025u2=1.500625+73.5u+900u2
2455.2025−2455.2025u2=1.500625+73.5u+900u2
2455.2025−2455.2025u2=1.500625+73.5u+900u2
解く 2455.2025−2455.2025u2=1.500625+73.5u+900u2:u=2−0.02190…+2.92573…,u=2−0.02190…−2.92573…
2455.2025−2455.2025u2=1.500625+73.5u+900u2
辺を交換する1.500625+73.5u+900u2=2455.2025−2455.2025u2
2455.2025u2を左側に移動します
1.500625+73.5u+900u2=2455.2025−2455.2025u2
両辺に2455.2025u2を足す1.500625+73.5u+900u2+2455.2025u2=2455.2025−2455.2025u2+2455.2025u2
簡素化1.500625+73.5u+3355.2025u2=2455.2025
1.500625+73.5u+3355.2025u2=2455.2025
2455.2025を左側に移動します
1.500625+73.5u+3355.2025u2=2455.2025
両辺から2455.2025を引く1.500625+73.5u+3355.2025u2−2455.2025=2455.2025−2455.2025
簡素化3355.2025u2+73.5u−2453.701875=0
3355.2025u2+73.5u−2453.701875=0
以下で両辺を割る3355.20253355.20253355.2025u2+3355.202573.5u−3355.20252453.701875=3355.20250
標準的な形式で書く ax2+bx+c=0u2+0.02190…u−0.73131…=0
解くとthe二次式
u2+0.02190…u−0.73131…=0
二次Equationの公式:
次の場合: a=1,b=0.02190…,c=−0.73131…u1,2=2⋅1−0.02190…±0.02190…2−4⋅1⋅(−0.73131…)
u1,2=2⋅1−0.02190…±0.02190…2−4⋅1⋅(−0.73131…)
0.02190…2−4⋅1⋅(−0.73131…)=2.92573…
0.02190…2−4⋅1⋅(−0.73131…)
規則を適用 −(−a)=a=0.02190…2+4⋅1⋅0.73131…
数を乗じる:4⋅1⋅0.73131…=2.92525…=0.02190…2+2.92525…
0.02190…2=0.00047…=0.00047…+2.92525…
数を足す:0.00047…+2.92525…=2.92573…=2.92573…
u1,2=2⋅1−0.02190…±2.92573…
解を分離するu1=2⋅1−0.02190…+2.92573…,u2=2⋅1−0.02190…−2.92573…
u=2⋅1−0.02190…+2.92573…:2−0.02190…+2.92573…
2⋅1−0.02190…+2.92573…
数を乗じる:2⋅1=2=2−0.02190…+2.92573…
u=2⋅1−0.02190…−2.92573…:2−0.02190…−2.92573…
2⋅1−0.02190…−2.92573…
数を乗じる:2⋅1=2=2−0.02190…−2.92573…
二次equationの解:u=2−0.02190…+2.92573…,u=2−0.02190…−2.92573…
u=2−0.02190…+2.92573…,u=2−0.02190…−2.92573…
解を検算する:u=2−0.02190…+2.92573…真,u=2−0.02190…−2.92573…偽
49.551−u2−30u=1.225 に当てはめて解を確認する
equationに一致しないものを削除する。
挿入 u=2−0.02190…+2.92573…:真
49.551−(2−0.02190…+2.92573…)2−30(2−0.02190…+2.92573…)=1.225
49.551−(2−0.02190…+2.92573…)2−30(2−0.02190…+2.92573…)=1.225
49.551−(2−0.02190…+2.92573…)2−30(2−0.02190…+2.92573…)
括弧を削除する: (a)=a=49.551−(2−0.02190…+2.92573…)2−30⋅2−0.02190…+2.92573…
49.551−(2−0.02190…+2.92573…)2=49.550.28718…
49.551−(2−0.02190…+2.92573…)2
1−(2−0.02190…+2.92573…)2=0.28718…
1−(2−0.02190…+2.92573…)2
(2−0.02190…+2.92573…)2=0.71281…
(2−0.02190…+2.92573…)2
2−0.02190…+2.92573…=21.68857…
2−0.02190…+2.92573…
2.92573…=1.71047…=2−0.02190…+1.71047…
数を足す/引く:−0.02190…+1.71047…=1.68857…=21.68857…
=(21.68857…)2
指数の規則を適用する: (ba)c=bcac=221.68857…2
1.68857…2=2.85126…=222.85126…
22=4=42.85126…
数を割る:42.85126…=0.71281…=0.71281…
=1−0.71281…
数を引く:1−0.71281…=0.28718…=0.28718…
=49.550.28718…
30⋅2−0.02190…+2.92573…=25.32855…
30⋅2−0.02190…+2.92573…
2−0.02190…+2.92573…=21.68857…
2−0.02190…+2.92573…
2.92573…=1.71047…=2−0.02190…+1.71047…
数を足す/引く:−0.02190…+1.71047…=1.68857…=21.68857…
=30⋅21.68857…
分数を乗じる: a⋅cb=ca⋅b=21.68857…⋅30
数を乗じる:1.68857…⋅30=50.65711…=250.65711…
数を割る:250.65711…=25.32855…=25.32855…
=49.550.28718…−25.32855…
49.550.28718…=26.55355…
49.550.28718…
0.28718…=0.53589…=0.53589…⋅49.55
数を乗じる:49.55⋅0.53589…=26.55355…=26.55355…
=26.55355…−25.32855…
数を引く:26.55355…−25.32855…=1.225=1.225
1.225=1.225
真
挿入 u=2−0.02190…−2.92573…:偽
49.551−(2−0.02190…−2.92573…)2−30(2−0.02190…−2.92573…)=1.225
49.551−(2−0.02190…−2.92573…)2−30(2−0.02190…−2.92573…)=50.74648…
49.551−(2−0.02190…−2.92573…)2−30(2−0.02190…−2.92573…)
括弧を削除する: (a)=a=49.551−(2−0.02190…−2.92573…)2−30⋅2−0.02190…−2.92573…
49.551−(2−0.02190…−2.92573…)2=49.550.24971…
49.551−(2−0.02190…−2.92573…)2
1−(2−0.02190…−2.92573…)2=0.24971…
1−(2−0.02190…−2.92573…)2
(2−0.02190…−2.92573…)2=0.75028…
(2−0.02190…−2.92573…)2
2−0.02190…−2.92573…=−21.73238…
2−0.02190…−2.92573…
2.92573…=1.71047…=2−0.02190…−1.71047…
数を引く:−0.02190…−1.71047…=−1.73238…=2−1.73238…
分数の規則を適用する: b−a=−ba=−21.73238…
=(−21.73238…)2
指数の規則を適用する: n が偶数であれば (−a)n=an(−21.73238…)2=(21.73238…)2=(21.73238…)2
指数の規則を適用する: (ba)c=bcac=221.73238…2
1.73238…2=3.00115…=223.00115…
22=4=43.00115…
数を割る:43.00115…=0.75028…=0.75028…
=1−0.75028…
数を引く:1−0.75028…=0.24971…=0.24971…
=49.550.24971…
30⋅2−0.02190…−2.92573…=−25.98574…
30⋅2−0.02190…−2.92573…
2−0.02190…−2.92573…=−21.73238…
2−0.02190…−2.92573…
2.92573…=1.71047…=2−0.02190…−1.71047…
数を引く:−0.02190…−1.71047…=−1.73238…=2−1.73238…
分数の規則を適用する: b−a=−ba=−21.73238…
=30(−21.73238…)
括弧を削除する: (−a)=−a=−30⋅21.73238…
分数を乗じる: a⋅cb=ca⋅b=−21.73238…⋅30
数を乗じる:1.73238…⋅30=51.97148…=−251.97148…
数を割る:251.97148…=25.98574…=−25.98574…
=49.550.24971…−(−25.98574…)
規則を適用 −(−a)=a=49.550.24971…+25.98574…
49.550.24971…=24.76074…
49.550.24971…
0.24971…=0.49971…=0.49971…⋅49.55
数を乗じる:49.55⋅0.49971…=24.76074…=24.76074…
=24.76074…+25.98574…
数を足す:24.76074…+25.98574…=50.74648…=50.74648…
50.74648…=1.225
偽
解はu=2−0.02190…+2.92573…
代用を戻す u=sin(θ)sin(θ)=2−0.02190…+2.92573…
sin(θ)=2−0.02190…+2.92573…
sin(θ)=2−0.02190…+2.92573…:θ=arcsin(2−0.02190…+2.92573…)+2πn,θ=π−arcsin(2−0.02190…+2.92573…)+2πn
sin(θ)=2−0.02190…+2.92573…
三角関数の逆数プロパティを適用する
sin(θ)=2−0.02190…+2.92573…
以下の一般解 sin(θ)=2−0.02190…+2.92573…sin(x)=a⇒x=arcsin(a)+2πn,x=π−arcsin(a)+2πnθ=arcsin(2−0.02190…+2.92573…)+2πn,θ=π−arcsin(2−0.02190…+2.92573…)+2πn
θ=arcsin(2−0.02190…+2.92573…)+2πn,θ=π−arcsin(2−0.02190…+2.92573…)+2πn
すべての解を組み合わせるθ=arcsin(2−0.02190…+2.92573…)+2πn,θ=π−arcsin(2−0.02190…+2.92573…)+2πn
10進法形式で解を証明するθ=1.00522…+2πn,θ=π−1.00522…+2πn