Question

Use suitable identities to expand..... (3a+2b-5c)2
$(3a + 2b - 5c) {}^{2}$
​

Answer 1

Step-by-step explanation:

(3a+3b-5c)2

3a×2+3b×2-5c×2

6a+6b+10c

+10c because (-)×(-)=(+)

Answer 2

Step-by-step explanation:

We have :(3a+2b-5c) ²

Identity Used:-

(x+y+z) ²= x²+y²+z²+2( xy + yz + zx)

Take:

x=3a,

y=2b,

z= -5c

A/q ==>{3a+2b+(-5c)}2:

= (3a)²+(2b)²+(-5c)²+2(3a*2b)+{2b*(-5c)} +{3a*(-5c)}

=9a²+4b²+25c²+2{6ab+(-10bc)+(-15ac)}

=9a²+4b²+25c²+12ab-20bc-30ac

Therefore,(3a+2b-5c)²=9a²+4b²+25c²+12ab-20bc-30ac {Ans}

Hope it's helps...