1)cost/(1+cost)+cost/(1-sint)=((cost(1-sint+1+sint))/(1+sint)*(1-sint)=2cost/cos^2t=2/cost
2)tqx+1/(1-ctqx)=1/ctqx+1/(1-ctqx)=(1-ctqx+ctqx)/(ctqx(-ctqx)=1/(ctqx-ctq^2x)
1-y^11y^5=y^16
2-n^0n^8=1*n^8=n^8
(m²+3m-4)/(m-1)=m+4)
m²+3m-4=0 D=25
m₁=1 m₂=-4 ⇒
(m-1)*(m+4)/(m-1)=m+4
m+4≡m+4.
<span>16х^2-24ху+9у^2-4х+3у=4х(4х-6у-1)+3у(3у+1)=(4х-6у-1)(3у+1)(4х+3у)</span>
A3.
2^log₂7+2*log₅15-log₅9=7+log₅(15²/9)=7+log₅25=7+2=9