Trigonometría del 1

Logaritmos:

LogaB=X...a^x=B

Log a*b= loga+logb

Loga/b=loga-logb

logx^a=alogx

Trigonometria:

sen^2+cos^2=1  1+cotg^2=cosec^2  tg^2+1=sec^2

sen(a+b)=senAcosB+cosAsenB 

cos(a+b)=cosAcosB+senAsenB

tg(a+b)=sen(a+b)/cos(a+b)=seAcosB+cosAsenB/cosAcosB+senAsenB=tgA+tgB/1-tgAtgB

sen(a-b)=sen(a+(-b))=senAcos(-B)+cosAsen(-B)=senAcosB+cosAsen(-B)=senAcosB-cosAsenB

cos(a-b)=cos(a+(-b))=cosacos(-B)-senasen(-B)=cosAcosB-senA(-senB)=cosAcosB+senAsenB

tg(a-b)(tga+(-b))= tgA+tg(-b)/1-tgAtg-B=tgA+(-tgB)/1-tgA(-tgB)=tgA-tgB/1+TgAtgB

sen2a=sen(a+a)=senAcosA+cosAsenA=2senAcosA

cos2a=cos(a+a)=cosAcosA-senAsenA=cos^2A-sen^2A

tg2A=tg(a+a)=tgA+tgA/1-tgAtgA=2tgA/1-tg^2A

senA+senB=sen(a+b)+sen(a-b)=sanAsanB+cosAcosB+senAcosB-cosAsenB=2senAcosB=2sen(A+B/2)cos(A-B/2)

Teorema del coseno:

Partes de : B^2=X^2+H^2

                A^2=(C-X)^2+H^2 

------------Tachas H cambiando signo-------------------

A^2-B^2=(C-X)^2-X^2=}A^2-B^2=C^2+X^2-2CX-X^2  } A^2=B^2+C^2-2CX} 

A^2=B^2+C^2-2CcosA

B^2=A^2+C^2-2CcosB

C^2=B^2+A^2-2cosC

Teorema del seno:

senB=h/c==h=CsenB         CsenB=bsenC

senC=h/b==h=BsenC        C/senC=B/senB

Utiliza seno si sabes un angulo y su lado opuesto, si no, coseno