해법
3tan(x)+cot(x)<5sin(x)
해법
2π+2πn<x<π+2πnor23π+2πn<x<2π+2πn
+2
간격 표기법
(2π+2πn,π+2πn)∪(23π+2πn,2π+2πn)소수
1.57079…+2πn<x<3.14159…+2πnor4.71238…+2πn<x<6.28318…+2πn솔루션 단계
3tan(x)+cot(x)<5sin(x)
5sin(x)를 왼쪽으로 이동
3tan(x)+cot(x)<5sin(x)
빼다 5sin(x) 양쪽에서3tan(x)+cot(x)−5sin(x)<5sin(x)−5sin(x)
3tan(x)+cot(x)−5sin(x)<0
3tan(x)+cot(x)−5sin(x)<0
주기성 3tan(x)+cot(x)−5sin(x):2π
주기 함수의 합의 복합 주기성은 주기의 최소 공배수이다3tan(x),cot(x),5sin(x)
주기성 3tan(x):π
주기성 a⋅tan(bx+c)+d=∣b∣주기성tan(x)주기성 tan(x)이다 π=∣1∣π
단순화=π
주기성 cot(x):π
주기성 cot(x)이다 π=π
주기성 5sin(x):2π
주기성 a⋅sin(bx+c)+d=∣b∣주기성sin(x)주기성 sin(x)이다 2π=∣1∣2π
단순화=2π
합계 기간: π,π,2π
=2π
죄로 표현하라, 왜냐하면
3tan(x)+cot(x)−5sin(x)<0
기본 삼각형 항등식 사용: tan(x)=cos(x)sin(x)3⋅cos(x)sin(x)+cot(x)−5sin(x)<0
기본 삼각형 항등식 사용: cot(x)=sin(x)cos(x)3⋅cos(x)sin(x)+sin(x)cos(x)−5sin(x)<0
3⋅cos(x)sin(x)+sin(x)cos(x)−5sin(x)<0
3⋅cos(x)sin(x)+sin(x)cos(x)−5sin(x)간소화하다 :cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)
3⋅cos(x)sin(x)+sin(x)cos(x)−5sin(x)
3⋅cos(x)sin(x)곱하다 :cos(x)3sin(x)
3⋅cos(x)sin(x)
다중 분수: a⋅cb=ca⋅b=cos(x)sin(x)⋅3
=cos(x)3sin(x)+sin(x)cos(x)−5sin(x)
요소를 분수로 변환: 5sin(x)=15sin(x)=cos(x)sin(x)⋅3+sin(x)cos(x)−15sin(x)
cos(x),sin(x),1 의 최소 공배수:cos(x)sin(x)
cos(x),sin(x),1
최저공통승수 (LCM)
인수식 중 하나 이상에 나타나는 요인으로 구성된 식을 계산합니다=cos(x)sin(x)
LCM을 기준으로 분수 조정
각 분자를 곱하는 데 필요한 동일한 양으로 곱하시오
해당 분모를 LCM으로 변환합니다 cos(x)sin(x)
위해서 cos(x)sin(x)⋅3:분모와 분자를 곱하다 sin(x)cos(x)sin(x)⋅3=cos(x)sin(x)sin(x)⋅3sin(x)=cos(x)sin(x)3sin2(x)
위해서 sin(x)cos(x):분모와 분자를 곱하다 cos(x)sin(x)cos(x)=sin(x)cos(x)cos(x)cos(x)=cos(x)sin(x)cos2(x)
위해서 15sin(x):분모와 분자를 곱하다 cos(x)sin(x)15sin(x)=1⋅cos(x)sin(x)5sin(x)cos(x)sin(x)=cos(x)sin(x)5sin2(x)cos(x)
=cos(x)sin(x)3sin2(x)+cos(x)sin(x)cos2(x)−cos(x)sin(x)5sin2(x)cos(x)
분모가 같기 때문에, 분수를 합친다: ca±cb=ca±b=cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)
cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)<0
의 0 및 정의되지 않은 점 찾기 cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)위해서 0≤x<2π
0을 찾으려면 부등식을 0으로 설정하십시오cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)=0
cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)=0,0≤x<2π:솔루션 없음 x∈R
cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)=0,0≤x<2π
g(x)f(x)=0⇒f(x)=03sin2(x)+cos2(x)−5sin2(x)cos(x)=0
삼각성을 사용하여 다시 쓰기
cos2(x)+3sin2(x)−5cos(x)sin2(x)
피타고라스 정체성 사용: cos2(x)+sin2(x)=1sin2(x)=1−cos2(x)=cos2(x)+3(1−cos2(x))−5cos(x)(1−cos2(x))
cos2(x)+3(1−cos2(x))−5cos(x)(1−cos2(x))간소화하다 :−2cos2(x)−5cos(x)+5cos3(x)+3
cos2(x)+3(1−cos2(x))−5cos(x)(1−cos2(x))
3(1−cos2(x))확대한다:3−3cos2(x)
3(1−cos2(x))
분배 법칙 적용: a(b−c)=ab−aca=3,b=1,c=cos2(x)=3⋅1−3cos2(x)
숫자를 곱하시오: 3⋅1=3=3−3cos2(x)
=cos2(x)+3−3cos2(x)−5cos(x)(1−cos2(x))
−5cos(x)(1−cos2(x))확대한다:−5cos(x)+5cos3(x)
−5cos(x)(1−cos2(x))
분배 법칙 적용: a(b−c)=ab−aca=−5cos(x),b=1,c=cos2(x)=−5cos(x)⋅1−(−5cos(x))cos2(x)
마이너스 플러스 규칙 적용−(−a)=a=−5⋅1⋅cos(x)+5cos2(x)cos(x)
−5⋅1⋅cos(x)+5cos2(x)cos(x)단순화하세요:−5cos(x)+5cos3(x)
−5⋅1⋅cos(x)+5cos2(x)cos(x)
5⋅1⋅cos(x)=5cos(x)
5⋅1⋅cos(x)
숫자를 곱하시오: 5⋅1=5=5cos(x)
5cos2(x)cos(x)=5cos3(x)
5cos2(x)cos(x)
지수 규칙 적용: ab⋅ac=ab+ccos2(x)cos(x)=cos2+1(x)=5cos2+1(x)
숫자 추가: 2+1=3=5cos3(x)
=−5cos(x)+5cos3(x)
=−5cos(x)+5cos3(x)
=cos2(x)+3−3cos2(x)−5cos(x)+5cos3(x)
cos2(x)+3−3cos2(x)−5cos(x)+5cos3(x)단순화하세요:−2cos2(x)−5cos(x)+5cos3(x)+3
cos2(x)+3−3cos2(x)−5cos(x)+5cos3(x)
집단적 용어=cos2(x)−3cos2(x)−5cos(x)+5cos3(x)+3
유사 요소 추가: cos2(x)−3cos2(x)=−2cos2(x)=−2cos2(x)−5cos(x)+5cos3(x)+3
=−2cos2(x)−5cos(x)+5cos3(x)+3
=−2cos2(x)−5cos(x)+5cos3(x)+3
3−2cos2(x)−5cos(x)+5cos3(x)=0
대체로 해결
3−2cos2(x)−5cos(x)+5cos3(x)=0
하게: cos(x)=u3−2u2−5u+5u3=0
3−2u2−5u+5u3=0:u≈−1.06603…
3−2u2−5u+5u3=0
표준 양식으로 작성 anxn+…+a1x+a0=05u3−2u2−5u+3=0
다음을 위한 하나의 솔루션 찾기 5u3−2u2−5u+3=0 뉴턴-랩슨을 이용하여:u≈−1.06603…
5u3−2u2−5u+3=0
뉴턴-랩슨 근사 정의
f(u)=5u3−2u2−5u+3
f′(u)찾다 :15u2−4u−5
dud(5u3−2u2−5u+3)
합계/차이 규칙 적용: (f±g)′=f′±g′=dud(5u3)−dud(2u2)−dud(5u)+dud(3)
dud(5u3)=15u2
dud(5u3)
정수를 빼라: (a⋅f)′=a⋅f′=5dud(u3)
전원 규칙을 적용합니다: dxd(xa)=a⋅xa−1=5⋅3u3−1
단순화=15u2
dud(2u2)=4u
dud(2u2)
정수를 빼라: (a⋅f)′=a⋅f′=2dud(u2)
전원 규칙을 적용합니다: dxd(xa)=a⋅xa−1=2⋅2u2−1
단순화=4u
dud(5u)=5
dud(5u)
정수를 빼라: (a⋅f)′=a⋅f′=5dudu
공통 도함수 적용: dudu=1=5⋅1
단순화=5
dud(3)=0
dud(3)
상수의 도함수: dxd(a)=0=0
=15u2−4u−5+0
단순화=15u2−4u−5
렛 u0=−1계산하다 un+1 까지 Δun+1<0.000001
u1=−1.07142…:Δu1=0.07142…
f(u0)=5(−1)3−2(−1)2−5(−1)+3=1f′(u0)=15(−1)2−4(−1)−5=14u1=−1.07142…
Δu1=∣−1.07142…−(−1)∣=0.07142…Δu1=0.07142…
u2=−1.06606…:Δu2=0.00536…
f(u1)=5(−1.07142…)3−2(−1.07142…)2−5(−1.07142…)+3=−0.08855…f′(u1)=15(−1.07142…)2−4(−1.07142…)−5=16.50510…u2=−1.06606…
Δu2=∣−1.06606…−(−1.07142…)∣=0.00536…Δu2=0.00536…
u3=−1.06603…:Δu3=0.00003…
f(u2)=5(−1.06606…)3−2(−1.06606…)2−5(−1.06606…)+3=−0.00051…f′(u2)=15(−1.06606…)2−4(−1.06606…)−5=16.31161…u3=−1.06603…
Δu3=∣−1.06603…−(−1.06606…)∣=0.00003…Δu3=0.00003…
u4=−1.06603…:Δu4=1.11867E−9
f(u3)=5(−1.06603…)3−2(−1.06603…)2−5(−1.06603…)+3=−1.8246E−8f′(u3)=15(−1.06603…)2−4(−1.06603…)−5=16.31046…u4=−1.06603…
Δu4=∣−1.06603…−(−1.06603…)∣=1.11867E−9Δu4=1.11867E−9
u≈−1.06603…
긴 나눗셈 적용:u+1.06603…5u3−2u2−5u+3=5u2−7.33015…u+2.81417…
5u2−7.33015…u+2.81417…≈0
다음을 위한 하나의 솔루션 찾기 5u2−7.33015…u+2.81417…=0 뉴턴-랩슨을 이용하여:솔루션 없음 u∈R
5u2−7.33015…u+2.81417…=0
뉴턴-랩슨 근사 정의
f(u)=5u2−7.33015…u+2.81417…
f′(u)찾다 :10u−7.33015…
dud(5u2−7.33015…u+2.81417…)
합계/차이 규칙 적용: (f±g)′=f′±g′=dud(5u2)−dud(7.33015…u)+dud(2.81417…)
dud(5u2)=10u
dud(5u2)
정수를 빼라: (a⋅f)′=a⋅f′=5dud(u2)
전원 규칙을 적용합니다: dxd(xa)=a⋅xa−1=5⋅2u2−1
단순화=10u
dud(7.33015…u)=7.33015…
dud(7.33015…u)
정수를 빼라: (a⋅f)′=a⋅f′=7.33015…dudu
공통 도함수 적용: dudu=1=7.33015…⋅1
단순화=7.33015…
dud(2.81417…)=0
dud(2.81417…)
상수의 도함수: dxd(a)=0=0
=10u−7.33015…+0
단순화=10u−7.33015…
렛 u0=0계산하다 un+1 까지 Δun+1<0.000001
u1=0.38391…:Δu1=0.38391…
f(u0)=5⋅02−7.33015…⋅0+2.81417…=2.81417…f′(u0)=10⋅0−7.33015…=−7.33015…u1=0.38391…
Δu1=∣0.38391…−0∣=0.38391…Δu1=0.38391…
u2=0.59502…:Δu2=0.21110…
f(u1)=5⋅0.38391…2−7.33015…⋅0.38391…+2.81417…=0.73696…f′(u1)=10⋅0.38391…−7.33015…=−3.49098…u2=0.59502…
Δu2=∣0.59502…−0.38391…∣=0.21110…Δu2=0.21110…
u3=0.75649…:Δu3=0.16147…
f(u2)=5⋅0.59502…2−7.33015…⋅0.59502…+2.81417…=0.22282…f′(u2)=10⋅0.59502…−7.33015…=−1.37992…u3=0.75649…
Δu3=∣0.75649…−0.59502…∣=0.16147…Δu3=0.16147…
u4=0.20133…:Δu4=0.55516…
f(u3)=5⋅0.75649…2−7.33015…⋅0.75649…+2.81417…=0.13037…f′(u3)=10⋅0.75649…−7.33015…=0.23484…u4=0.20133…
Δu4=∣0.20133…−0.75649…∣=0.55516…Δu4=0.55516…
u5=0.49118…:Δu5=0.28984…
f(u4)=5⋅0.20133…2−7.33015…⋅0.20133…+2.81417…=1.54101…f′(u4)=10⋅0.20133…−7.33015…=−5.31676…u5=0.49118…
Δu5=∣0.49118…−0.20133…∣=0.28984…Δu5=0.28984…
u6=0.66486…:Δu6=0.17368…
f(u5)=5⋅0.49118…2−7.33015…⋅0.49118…+2.81417…=0.42003…f′(u5)=10⋅0.49118…−7.33015…=−2.41835…u6=0.66486…
Δu6=∣0.66486…−0.49118…∣=0.17368…Δu6=0.17368…
u7=0.88620…:Δu7=0.22133…
f(u6)=5⋅0.66486…2−7.33015…⋅0.66486…+2.81417…=0.15083…f′(u6)=10⋅0.66486…−7.33015…=−0.68147…u7=0.88620…
Δu7=∣0.88620…−0.66486…∣=0.22133…Δu7=0.22133…
u8=0.72630…:Δu8=0.15990…
f(u7)=5⋅0.88620…2−7.33015…⋅0.88620…+2.81417…=0.24495…f′(u7)=10⋅0.88620…−7.33015…=1.53190…u8=0.72630…
Δu8=∣0.72630…−0.88620…∣=0.15990…Δu8=0.15990…
u9=2.63145…:Δu9=1.90514…
f(u8)=5⋅0.72630…2−7.33015…⋅0.72630…+2.81417…=0.12784…f′(u8)=10⋅0.72630…−7.33015…=−0.06710…u9=2.63145…
Δu9=∣2.63145…−0.72630…∣=1.90514…Δu9=1.90514…
u10=1.67551…:Δu10=0.95594…
f(u9)=5⋅2.63145…2−7.33015…⋅2.63145…+2.81417…=18.14798…f′(u9)=10⋅2.63145…−7.33015…=18.98439…u10=1.67551…
Δu10=∣1.67551…−2.63145…∣=0.95594…Δu10=0.95594…
u11=1.19072…:Δu11=0.48478…
f(u10)=5⋅1.67551…2−7.33015…⋅1.67551…+2.81417…=4.56912…f′(u10)=10⋅1.67551…−7.33015…=9.42497…u11=1.19072…
Δu11=∣1.19072…−1.67551…∣=0.48478…Δu11=0.48478…
u12=0.93398…:Δu12=0.25673…
f(u11)=5⋅1.19072…2−7.33015…⋅1.19072…+2.81417…=1.17510…f′(u11)=10⋅1.19072…−7.33015…=4.57708…u12=0.93398…
Δu12=∣0.93398…−1.19072…∣=0.25673…Δu12=0.25673…
u13=0.77000…:Δu13=0.16398…
f(u12)=5⋅0.93398…2−7.33015…⋅0.93398…+2.81417…=0.32956…f′(u12)=10⋅0.93398…−7.33015…=2.00972…u13=0.77000…
Δu13=∣0.77000…−0.93398…∣=0.16398…Δu13=0.16398…
u14=0.40647…:Δu14=0.36352…
f(u13)=5⋅0.77000…2−7.33015…⋅0.77000…+2.81417…=0.13445…f′(u13)=10⋅0.77000…−7.33015…=0.36986…u14=0.40647…
Δu14=∣0.40647…−0.77000…∣=0.36352…Δu14=0.36352…
해결 방법을 찾을 수 없습니다
해결책은u≈−1.06603…
뒤로 대체 u=cos(x)cos(x)≈−1.06603…
cos(x)≈−1.06603…
cos(x)=−1.06603…,0≤x<2π:해결책 없음
cos(x)=−1.06603…,0≤x<2π
−1≤cos(x)≤1해결책없음
모든 솔루션 결합솔루션없음x∈R
정의되지 않은 점 찾기:x=2π,x=23π,x=0,x=π
분모의 0 찾기cos(x)sin(x)=0
각 부분을 개별적으로 해결cos(x)=0orsin(x)=0
cos(x)=0,0≤x<2π:x=2π,x=23π
cos(x)=0,0≤x<2π
일반 솔루션 cos(x)=0
cos(x) 주기율표 2πn 주기:
x06π4π3π2π32π43π65πcos(x)12322210−21−22−23xπ67π45π34π23π35π47π611πcos(x)−1−23−22−210212223
x=2π+2πn,x=23π+2πn
x=2π+2πn,x=23π+2πn
범위에 맞는 솔루션 0≤x<2πx=2π,x=23π
sin(x)=0,0≤x<2π:x=0,x=π
sin(x)=0,0≤x<2π
일반 솔루션 sin(x)=0
sin(x) 주기율표 2πn 주기:
x06π4π3π2π32π43π65πsin(x)02122231232221xπ67π45π34π23π35π47π611πsin(x)0−21−22−23−1−23−22−21
x=0+2πn,x=π+2πn
x=0+2πn,x=π+2πn
x=0+2πn해결 :x=2πn
x=0+2πn
0+2πn=2πnx=2πn
x=2πn,x=π+2πn
범위에 맞는 솔루션 0≤x<2πx=0,x=π
모든 솔루션 결합x=2π,x=23π,x=0,x=π
0,2π,π,23π
간격 식별0<x<2π,2π<x<π,π<x<23π,23π<x<2π
표로 요약:3sin2(x)+cos2(x)−5sin2(x)cos(x)cos(x)sin(x)cos(x)sin(x)3sin2(x)+cos2(x)−5sin2(x)cos(x)x=0++0한정되지않은0<x<2π++++x=2π+0+한정되지않은2π<x<π+−+−x=π+−0한정되지않은π<x<23π+−−+x=23π+0−한정되지않은23π<x<2π++−−x=2π++0한정되지않은
필요한 조건을 충족하는 간격을 식별합니다: <02π<x<πor23π<x<2π
의 주기성을 적용합니다 3tan(x)+cot(x)−5sin(x)2π+2πn<x<π+2πnor23π+2πn<x<2π+2πn