Math, asked by boythebest24, 1 year ago

3 to the power x + 2 + 3 to the power minus x equal to 10​

Answers

Answered by Anonymous
98

GOOD \:  \: MORNING \:  \\  \\ 3 {}^{(x + 2)}  + 3 {}^{ - x}  = 10 \\  \\ 3 {}^{x}  \times 3 {}^{2}  + 1 \div (3 {}^{x} ) = 10 \\  \\ put \:  \: 3 {}^{x}  = z \:  \:  \: we \: have \:  \\  \\ 9z {}^{2}  - 10z + 1 = 0 \\  \\  9z {}^{2}  - 9z - z + 1 = 0 \\  \\ 9z(z - 1) - 1(z - 1) = 0 \\  \\ (9z - 1) = 0 \:  \:  \: or \:  \: (z - 1) = 0 \\  \\ z = 1 \div 9 \:  \:  \:  \: or \:  \:  \:  \: z = 1 \\  \\  z = 3 {}^{ - 2}  \:  \:  \:  \: or \:  \:  \:  \: z = 1 \\  \\  \\ so \:  \: 3 {}^{x}  = 3 {}^{ - 2}  \:  \:  \: or \:  \:  \: 3 {}^{x}  = 3 {}^{0}  \:  \: becoz \: 3 {}^{0}  = 1 \\  \\ now \: compare \: powers \: of \: 3 \: we \: have \\  \\ x =  - 2 \:  \:  \: or \:  \: x = 0

Answered by anish2445
24

X=-2 and x=0

I think it is the correct answer

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