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2^2x +2^(x+2) -4.2³ = 0
2^2x + 2^x.2² - 4.2³= 0
(2^x)² +4.2^x - 4.8 = 0
Let 2^x = P
P² + 4P - 32 = 0
P² + 8P - 4P -32 = 0
P(P + 8) -4(P+8) = 0
(P - 4)(P+8) = 0
P = 4 , -8
2^x = 4 , -8
but we know, exponent is never negative so, 2^x ≠ -8
2^x = 4 = 2²
x = 2
hence, x =2
2^2x + 2^x.2² - 4.2³= 0
(2^x)² +4.2^x - 4.8 = 0
Let 2^x = P
P² + 4P - 32 = 0
P² + 8P - 4P -32 = 0
P(P + 8) -4(P+8) = 0
(P - 4)(P+8) = 0
P = 4 , -8
2^x = 4 , -8
but we know, exponent is never negative so, 2^x ≠ -8
2^x = 4 = 2²
x = 2
hence, x =2
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