How do you expand #(1+4x^4)^4#?

1 Answer
Dec 10, 2017

# (1+4x^4)^4=1+16x^4+96x^8 +256x^12+256x^16 .#

Explanation:

#(a + b)^n =(nC_0) a^nb^0+ (nC_1) a^(n-1)b^1 +(nC_2) a^(n-2)b^2 +...... (nC_n)b^n#

Here # (a=1 ; b=4x^4 , n= 4) :. 1^n=1 , x^0=1#

We know #nC_r= (n!)/(r!(n-r)!)#

# :. 4C_0=1 , 4C_1=4 , 4C_2=6 ,4C_3=4,4C_4=1#

#:. (1+x)^3= 1 + 3x+3x^2+x^3 :.#

#(1+4x^4)^4 = 1^4 + 4*1^3*4x^4+6*1^2*(4x^4)^2+4*1* (4x^4)^3 + (4x^4)^4#

#:. (1+4x^4)^4=1+16x^4+96x^8 +256x^12+256x^16#
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