matlab,system,equation , solve symbolic system of equations inside an array

## Question:

Tag: matlab,system,equation

sorry if it already has a answer..i tried other links but it didn't understand i have 2 1*63 array .landa and v. each of their members are syms. and each v member is a function of all landa members.i have already calculated v members and they are all symbolic equations function of landa1...landa63 for example v(2) is:

``````- (26032168169837596*landa_1_1)/1818071823710369 - (1248281001603436*landa_1_3)/86484908042379 - (52625347239733568*landa_1_4)/7261479255655197 - (6604602588458826*landa_1_5)/1360945351882651 - (13266428887920030*landa_1_6)/3627728680706743 - (13328946369600138*landa_1_7)/4532912553538921 - (13397783439780820*landa_1_8)/5437431490145639 - (4491362061290848*landa_1_9)/2113747029461023 - (13559659774820030*landa_1_10)/7244344326692733 - (6828247388123141*landa_1_11)/4073339103373161 - (3442454859315376*landa_1_12)/2266553892078633 - (6949066850632307*landa_1_13)/4983366792250084 - (7024497445184291*landa_1_14)/5433118949496761 - (889387874167034*landa_1_15)/735290915649273 - (3586600796756319*landa_1_16)/3049079330330816 - (7244103336161213*landa_1_17)/6322929884842724 - (3663915377012426*landa_1_18)/3273799694605737 - (7427507175063298*landa_1_19)/6772119170494125 - (7547295597229107*landa_1_20)/6996432151091905 - (1923338048147995*landa_1_21)/1805121116217713 - (7874362398733741*landa_1_22)/7444211507963693 - (4051684049941553*landa_1_23)/3833776207492451 - (8331733241914890*landa_1_24)/7845891307457161 - (8606531462572406*landa_1_25)/8023896565108419 - (8756096133405978*landa_1_26)/8112761886216707 - (4477082052693931*landa_1_29)/4189433684998512 - (4293059637590261*landa_1_30)/4233768184335278 - (4967757600021511*landa_1_32)/77075937264547968615886243233792 - (2274910796541161*landa_1_34)/8470743025804629 - (6028337215106101*landa_1_35)/16766874508660884 - (434117063192273*landa_1_36)/1036973999581658 - (3802611183306680*landa_1_37)/8207893792607821 - (8115962046780543*landa_1_38)/16239563076236596 - (4264630823999399*landa_1_39)/8031489540592591 - (382070995992493*landa_1_40)/654536108370494 - (1206382478629297*landa_1_41)/1919215219152206 - (5057377064996180*landa_1_42)/7454301295942339 - (5238466105690712*landa_1_43)/7231219638064483 - (5384852859880393*landa_1_44)/7007714246020179 - (56761628997640*landa_1_45)/69936892400419 - (5607644779348011*landa_1_46)/6559787230544288 - (5694155621326436*landa_1_47)/6335516873838327 - (5768331379800997*landa_1_48)/6111131481923240 - (5829886618525661*landa_1_49)/5895672906607196 - (5928984667335071*landa_1_50)/5447442533826811 - (1520446165159822*landa_1_52)/1137305157592641 - (409597577403863*landa_1_53)/272688134034879 - (12394543279688924*landa_1_54)/7280059714659769 - (832603741914514*landa_1_55)/425254609909857 - (12573597782885200*landa_1_56)/5477098860424583 - (6325031977448627*landa_1_57)/2287526886867664 - (6359844452086436*landa_1_58)/1836534772502583 - (25567126758252096*landa_1_59)/5543811068392643 - (51370713192797208*landa_1_60)/7494668753437699 - (25795907362066832*landa_1_61)/1976172947874511 - (20234459321830409375*landa_1_62)/454300612410998784 - (1299970916679950*landa_1_63)/91626708293577 - (288230376151711744*1049^(1/2)*landa_1_27)/8603414113545292505 - (5629499534213120*17146^(1/2)*landa_1_31)/729733163812670453 - (112589990684262400*19121^(1/2)*landa_1_33)/81400055837869623247 - (171136785840078848*20261^(1/2)*landa_1_51)/20255345682677877255 - (225179981368524800*40081^(1/2)*landa_1_28)/41535093106204407301
``````

now i want to solve each v(i) =0 so i have 63 equations(v(i)==0) and 63 unknown (landa(i)s). how shuould i solve this system?

Generally this is done (if the eq is in the format you have) with an `Ax=b` system.

Let me show you how to do it with a simple example of 2 eq with 2 unknowns.

``````3*l1-4*l2=3
5*l1 -3*l2=-4
``````

You can build the system as:

`x` (unknowns) will be a `unknowns x 1` size matrix. `A` is a `equations x unknonws` matrix `b` is a `equations x 1` matrix.

for the example:

``````A=[3 -4
5 -3];
b=[3
-4]
x=A\b;
``````

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