FUNCTION F(X) REALCI.C2.KX COMMON C1,C2,K F=X*(C2+X0**4/(C1-X)-K RETURN END SUBROUTINE NR(XO.F.DF.K.EPS.E.XN) X=XO T=10 FXN=FCX) 10 FX-FXN IF(K EQ.I)THEN DFX=DF(X) ELse H=1E-6*X DFX-(F(X+H)-FX)H END IF 20 XN=X-T*FX/DEX FXN=FOXN) IF(ABS(FXN).LT.ABS(FX))THEN R=(XN-XVX IF(ABS(R).GT.EPSyTHEN X=X G0T010 ELse RETURN ENDIE ELSE IF(T.GT.E)THEN T-0.5*T G0T020 ELSE IF(ABS(EXN GTEPSTHEN WRITE(*.61) END IF RETURN 61 FORMAT(/2X,'NO REAL ROOT WAS FOUND) END 4.运行结果。(20分)FUNCTION F(X) REAL C1,C2,K,X COMMON C1,C2,K F=X*(C2+X)**4/(C1-X)-K RETURN END SUBROUTINE NR(X0,F,DF,K,EPS,E,XN) X=X0 T=1.0 FXN=F(X) 10 FX=FXN IF(K.EQ.1)THEN DFX=DF(X) ELSE H=1E-6*X DFX=(F(X+H)-FX)/H END IF 20 XN=X-T*FX/DFX FXN=F(XN) IF(ABS(FXN).LT.ABS(FX))THEN R=(XN-X)/X IF(ABS(R).GT.EPS)THEN X=XN GOTO 10 ELSE RETURN END IF ELSE IF(T.GT.E)THEN T=0.5*T GOTO 20 ELSE IF(ABS(FXN).GT.EPS)THEN WRITE(*,61) END IF RETURN 61 FORMAT(/2X,'NO REAL ROOT WAS FOUND') END 4.运行结果。（20 分）