The equation can be written as 2^(3x) + 4 = 1/8 2^9x. Let t = 2^3x > t^3= 8t+32 > t=4 is a solution. [t^3-8t-32]/(t-4) = t^2+4t+8. t^2+4t+8 = 0 has the solutions t = -2 +/- 2 i which are complex and not acceptable. Thus t=4 > x = 2/3.
@woobjun25823 ай бұрын
The given can be ³√(t +4) = t/2 by letting t = 2³ˣ Cubing and rearringing, t³-8t -32 = 0; t³ -64 -8t +32 = 0; (t³ -4³) -8(t -4) = 0; (t -4)(t² +4t +16) -8(t -4) =0; (t -4)(t² +4t +8) =0 That is, t -4 =0 ; t = 4 or t² +4t +8 = 0; t = cmplx Therefore, t = 2³ˣ = 4 = 2² Finally 3x =2; x = 2/3
@abcekkdo37493 ай бұрын
X=2/3
@dorkmania3 ай бұрын
Simplifying RHS to (2^3x)/2 and substituting for LHS radical with t³ = (2^3x) + 4, the equation becomes (t³)^⅓ = (t³ - 4)/2 => 2t = t³ - 4 => t³ - 2t - 4 = 0 Using RRT and SDM, we get t = 2 as the only real solution. 2^3x - 4 = (2)³ => x = ⅔